tag:theconversation.com,2011:/au/topics/fishing-4998/articlesFishing – The Conversation2024-03-20T22:41:06Ztag:theconversation.com,2011:article/2246822024-03-20T22:41:06Z2024-03-20T22:41:06ZHow do halibut migrate? Clues are in their ear bones<figure><img src="https://images.theconversation.com/files/578657/original/file-20240220-18-5yndy5.jpg?ixlib=rb-1.1.0&rect=24%2C18%2C3953%2C2999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The habitats used throughout the halibut's life and the movements between them are difficult to characterize.</span> <span class="attribution"><span class="source">(Charlotte Gauthier)</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>Rising temperatures, changes in major currents, <a href="https://theconversation.com/why-the-st-lawrence-estuary-is-running-out-of-breath-184626">oxygen depletion at great depths</a>: the Gulf of St. Lawrence has undergone major changes in its environmental conditions in recent decades. That has put many species in danger and, as a consequence, made them more sensitive to the effects of fishing.</p>
<p>However, these changes are benefiting other species such as Atlantic halibut, which is beating records for its abundance and is presently seeing the highest stock in the Gulf of St. Lawrence in <a href="https://waves-vagues.dfo-mpo.gc.ca/library-bibliotheque/41206708.pdf">the last 60 years</a>.</p>
<p>As a biology researcher, I’d like to shed some light on some of the mysteries that still surround this unusual species.</p>
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<p><em>This article is part of our series, <a href="https://theconversation.com/ca-fr/topics/fleuve-saint-laurent-116908">The St. Lawrence River: In depth</a>.
Don’t miss new articles on this mythical river of remarkable beauty. Our experts look at its fauna, flora and history, and the issues it faces. This series is brought to you by <a href="https://theconversation.com/ca-fr">La Conversation</a>.</em></p>
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<h2>Atlantic halibut: champion of the Gulf of St. Lawrence</h2>
<p>Atlantic halibut is a flatfish that lives at the bottom of the estuary and gulf of the St. Lawrence. It is prized for its fine, firm white flesh, which is highly appreciated by consumers.</p>
<p>Halibut can grow to impressive sizes of <a href="https://www.tandfonline.com/doi/full/10.1080/23308249.2021.1948502">more than two metres</a>. Because of the quality of its flesh and its popularity on dinner plates, it is currently the most commercially valuable fish in the Gulf of St. Lawrence.</p>
<p>But this has not always been the case. In the 1950s, the adult, harvestable portion of halibut populations, known as the stock, <a href="https://academic.oup.com/icesjms/article/73/4/1104/2458915?login=false">suffered a major decline due to overfishing</a>.</p>
<p>If we want to continue to exploit this resource over the long term, we must not repeat the same mistakes we made in the past. To avoid these mistakes, it is vital to have a good understanding of the life cycle of halibut and the effects that fishing can have on the stock. So far, this has not been done to the fullest.</p>
<h2>The challenges for sustainable fishing</h2>
<p>The basic biology of Atlantic halibut is fairly well known. However, both the habitats they use throughout their lives and their movement between these places are more difficult to characterize.</p>
<p><a href="https://academic.oup.com/icesjms/article/77/7-8/2890/5923787?login=false">Recent studies</a> have placed satellite tags on halibut to record data on the depth and temperature of the water in which they are found, making it possible to accurately calculate their movement. By using this method, the researchers were able to identify the trajectories of adult halibut over a one-year period and discover that they reproduce in winter in the deep channels of the Gulf.</p>
<p>In the halibut’s different annual trajectories, the researchers observed that, in summer, some remain in the deep channels while others migrate to shallower areas.</p>
<p>Even with this new information, a number of questions remain, specifically about the youngest life stages, which are caught only anecdotally in the Gulf. Satellite tags also provide accurate information, but only over a one-year period, which doesn’t tell the whole story for a fish that can live up to 50 years.</p>
<p>With this in mind, the use of a new tool to study the entire life of fish becomes highly relevant.</p>
<h2>Ear bones to the rescue</h2>
<p>All bony fish have small calcareous structures in their inner ear called otoliths, or ear bones, which perform balance and hearing functions.</p>
<p>Otoliths develop at the very beginning of a fish’s life and grow at the same rate as the fish. Otoliths form annual growth rings that are comparable to those visible in tree trunks.</p>
<p>To grow, otoliths accumulate chemical elements that are found in the environment in which the fish swim. So, when the fish moves, the chemical elements accumulated in the otoliths will be different from one place to another. Each location is characterized by a unique combination of different concentrations of chemical elements. This is known as an elemental fingerprint. Identifying these fingerprints can provide us with crucial information about the movement of fish in different places throughout their lives.</p>
<p>I used this method of characterizing the chemical elements in otoliths to study the migratory patterns of Atlantic halibut in the Gulf of St. Lawrence.</p>
<h2>A wide range of migratory strategies</h2>
<p>To find out what concentrations of a chemical element correspond to the place where the fish was caught, we use the fingerprint of the otolith margin, i.e. the material at the end of the outermost ring of the otolith, which was accumulated last.</p>
<p>The concentrations of the elements found there are considered to be characteristic of the place where the fish was caught. By analyzing the margins of nearly 200 halibut otoliths from all over the Gulf, I was able to distinguish two basic fingerprints: one representative of surface waters (less than 100 metres deep) and one characteristic of deeper waters (more than 100 metres deep).</p>
<p>Once these fingerprints had been identified, I observed the concentration of chemical elements throughout the life of the fish so that I could associate each moment of life with either the surface water fingerprint or the deep-water fingerprint.</p>
<p>By separating the life of each individual into time spent in surface and deep waters, I was able to identify recurring patterns and group them into three different migratory strategies: residents, annual migrants and irregular migrants.</p>
<p>In this way, I was able to observe that halibut caught in the southern part of the Gulf were mainly annual migrants, and therefore undertake migrations between deep and shallow waters every year. However, in the northern part of the Gulf the majority are residents. Residents are fish that may have migrated early in their lives, but have settled permanently in deep waters before reaching maturity. Irregular migrants, on the other hand, show migrations on a more sporadic frequency, and are found in similar proportions throughout the study area.</p>
<h2>On the right track to optimal management</h2>
<p>My study is the first to offer a global view of the movements made by halibut over their entire lifetime.</p>
<p>This new information provides a better understanding of the structure of the stock and the diversity of migratory strategies that can be found within it.</p>
<p>Given that these strategies are distributed differently in different areas of the Gulf, we can ensure that we do not disproportionately target halibut using the same migratory strategy and avoid overfishing a single component of the stock.</p>
<p>In this way, it is possible to conserve this diversity, which helps the stock’s resilience in the face of the various changes that can occur.</p><img src="https://counter.theconversation.com/content/224682/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charlotte Gauthier has received funding from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Fondation de l'Université du Québec à Chicoutimi.
</span></em></p>Atlantic halibut are making a strong comeback in the Gulf of St. Lawrence. But how do we know where the fish move throughout their lives?Charlotte Gauthier, Étudiante au doctorat, Université du Québec à Chicoutimi (UQAC)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2250722024-03-19T14:07:41Z2024-03-19T14:07:41ZGreen lights on fishing nets could slash bycatch of sea turtles, says research<p><a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/j.1755-263X.2010.00105.x">Bycatch in fishing gear</a> is one of the <a href="https://www.worldwildlife.org/initiatives/protecting-turtles-from-the-threat-of-bycatch#:%7E:text=The%20single%20greatest%20threat%20to,and%20leatherbacks%20are%20especially%20vulnerable.">biggest threats</a> to sea turtles. But these creatures are particularly sensitive to <a href="https://www.cell.com/current-biology/pdfExtended/S0960-9822(21)01737-1">green light</a> so they’re less likely to get caught up in fishing nets fitted with green LED lights. </p>
<p>Since 2014, a team of marine biologists and I have been trialling ways to reduce turtle bycatch using lights in nets as a deterrent. Our <a href="https://www.sciencedirect.com/science/article/abs/pii/S0165783623003120#:%7E:text=Recently%2C%20net%20illumination%20has%20also,vulnerable%20species%20in%20set%20nets">recent study</a> shows that these lights can reduce bycatch by approximately 40%.</p>
<p>The adult <a href="https://www.worldwildlife.org/species/green-turtle">green turtles</a> I work with in Cyprus are over a metre long and weigh more than 100kg. The females nest and lay their eggs on Alagadi beach, <a href="https://www.wwf.org.uk/learn/fascinating-facts/marine-turtles#:%7E:text=It%27s%20survival%20of%20the%20fittest,from%20predators%20to%20marine%20plastics.">but only one in a thousand</a> of their tiny hatchlings will survive to adulthood decades later. </p>
<p>Once they have left their nesting beach, young green turtles often wash up dead. <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.12440">Thousands of turtles</a> are <a href="https://www.togetherforthemed.org/our-actions/cyprus-bycatch-7.html">killed annually</a> due to the activities of the Turkish Cypriot fleet alone. </p>
<p>With fish stocks in decline, fishers are using more nets to catch more fish – making bycatch more likely. That effectively negates any conservation efforts to help protect the young green turtles that feed on the coastal seagrass beds. </p>
<p>In this part of the Mediterranean Sea, fishers leave kilometres of net on the seabed overnight in these seagrass habitats. When they haul them in the morning they often find drowned turtles entangled. </p>
<p>But quantifying bycatch is not easy, especially in Cyprus, where hundreds of small fishing boats use different types of fishing gear. It’s even harder to identify the most dangerous fishing methods and prioritise possible solutions. </p>
<p>Together with local fishers and marine authorities, we have monitored impacts on marine life by deploying onboard observers and having fishers report their catches of dolphins, sea turtles, sharks, rays and monk seals.</p>
<p>The <a href="https://www.lindgren-pitman.com/products/lp-electralume-light-w-lithium-battery-add-videos">first lights</a> we trialled were effective, and Cypriot fishers corroborated the positive results from <a href="https://www.int-res.com/abstracts/meps/v408/p241-250/">trials in Mexico</a>. But they found these prototypes difficult to use, with moving metal parts that got tangled in the “set nets”. </p>
<p>These long panels of net which fishers deploy on the seabed are stored in buckets. Due to tangling, the lights needed to be attached and removed on every fishing trip.</p>
<p>They’d often stop working and were not specifically designed for these set nets. At US$40 (£30) per light, the cost of fitting 3km of net is US$12,000. That’s way more than the annual cost of replacing nets that have been cut to release turtles that have got caught.</p>
<p>To make this concept more feasible, we teamed up with Devon-based marine engineering company <a href="https://www.fishtekmarine.com/reduce-turtle-bycatch/">FishTek</a> in 2018 to develop a scalable solution. After years of trials, we developed a more efficient solution known as <a href="https://www.fishtekmarine.com/reduce-turtle-bycatch/">NetLights</a>, which costs just US$8 per light. </p>
<h2>Net illumination</h2>
<p>These battery-powered lights that can be easily attached to huge fishing nets reduce bycatch of turtles <a href="https://www.sciencedirect.com/science/article/abs/pii/S0165783623003120#:%7E:text=Recently%2C%20net%20illumination%20has%20also,vulnerable%20species%20in%20set%20nets">by around 40%</a>. But more trials are needed. </p>
<p>Because the green turtles living around the Cyprus coast keep dying, there aren’t that many of them, so catch rates remain low. Over time, more trials will provide more accurate results. </p>
<p>Thousands of NetLights have been made available to 50 fishers in Cyprus as part of a broader trial. Most are pleased with the target catch rates and ask for more. They’d be most likely to use them if costs are subsidised or if bycatch reduction tech like this is made a legal requirement to safeguard turtles from particular types of fishing net. </p>
<p>Every fisher uses a slightly different net set up and it’s hard to please them all. Ideally, the lights need to be slightly smaller, lighter and more buoyant so that they can replace the floats that fishers use to stand the nets in the water, without adding more bulk. </p>
<h2>Other solutions</h2>
<p>Aside from training fishers to rescue turtles that get entangled, other existing bycatch reduction methods include <a href="https://www.youtube.com/watch?v=sTuB88KaIpQ">turtle excluder devices</a> that fit inside the neck of trawl nets. While small fish and shrimp can pass between the bars to the back of the net, larger turtles bump against the metal grid and can escape through a flap in the mesh net.</p>
<p>In the US, bottom trawlers catching shrimp have to use <a href="https://en.wikipedia.org/wiki/Turtle_excluder_device#cite_note-4">turtle excluder devices</a> to provide an escape route for turtles and other large objects. </p>
<p>Circular fishing hooks which replace “J” shaped hooks are less likely to snag turtles. These have been <a href="https://www.seaturtlestatus.org/articles/2019/1/31/the-continuing-tale-of-circle-hooks-in-brazil">rolled out in large-scale commercial tuna and swordfish fleets</a> on the high seas. But their success has been variable and in some cases reduced target catch can make them economically unsustainable. </p>
<p>If not enforced by governments, measures like these may be requested from supermarkets as part of a bycatch audit to <a href="https://oceandisclosureproject.org/">promote best practice</a> within the supply chain.</p>
<p>In 2023, fisheries policy in northern Cyprus was updated to include some no-take zones and restricted areas to protect fish stocks and other vulnerable species. If properly enforced, both the sea turtles and the fish that fishers rely on will benefit from these measures. </p>
<p>By rolling out more NetLights in set net fisheries that are a top priority for bycatch management, and monitoring their effectiveness against the baseline data we now have, there is huge scope to improve the chance of survival for green turtles.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>Robin Snape works at Bluedot Associates UK and has received funding from MAVA Foundation, Lloyd's Register, People's Trust for Endangered Species, Shark Trust, British Chelonia Group and others.</span></em></p>Hi-tech green LED lights attached to fishing gear can act as a deterrent to turtles and help reduce bycatch by approximately 40%.Robin Snape, Associate Researcher, Centre for Ecology and Conservation, University of ExeterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2252572024-03-13T00:02:52Z2024-03-13T00:02:52ZSurviving fishing gear entanglement isn’t enough for endangered right whales – females still don’t breed afterward<figure><img src="https://images.theconversation.com/files/581023/original/file-20240311-30-7n1k5g.jpg?ixlib=rb-1.1.0&rect=15%2C7%2C5240%2C3936&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Endangered North Atlantic right whale Snow Cone, entangled in fishing rope, with her newborn calf off Georgia in 2021.</span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/WhaleEntanglement/e4dd953df8dc4ff8a1df41f310d9abda/photo">Georgia Department of Natural Resources/NOAA Permit #21731, via AP</a></span></figcaption></figure><p>It sounds like a crime show episode at sea: In late January 2024, federal regulators learned that a dead female North Atlantic right whale had been sighted near Martha’s Vineyard, Massachusetts. The whale was towed to shore, where more than 20 U.S. and Canadian scientists converged to perform a <a href="https://www.acvp.org/page/Necropsy">necropsy</a>, or animal autopsy. </p>
<p>On Feb. 14, the U.S. National Oceanic and Atmospheric Administration announced that the whale was #5120 in a <a href="https://rwcatalog.neaq.org/#/">catalog that tracks individual right whales</a>. Further, the agency said, rope that had been deeply embedded in the whale’s tail had likely come from <a href="https://www.fisheries.noaa.gov/national/endangered-species-conservation/north-atlantic-right-whale-updates">lobster fishing gear in Maine</a>. </p>
<p>Entanglement in fishing gear is a deadly threat to these <a href="https://www.iucnredlist.org/species/41712/178589687">critically endangered animals</a>. Scientists estimate that before commercial whaling scaled up in the 18th and 19th centuries, there may have been as many as <a href="https://doi.org/10.1111/cobi.12664">10,000 North Atlantic right whales</a>. Today, fewer than 360 individuals remain. <a href="http://dx.doi.org/10.3354/meps09923">Almost 90% of them</a> have been entangled at least once. </p>
<p>When whales become entangled in fishing gear, they use extra energy dragging it as they swim. If the rope is caught around their mouths, they may struggle to feed and slowly starve. Ropes wrapped around whales’ bodies, flippers or tails can cut into the animals’ skin and become <a href="https://theconversation.com/high-tech-fishing-gear-could-help-save-critically-endangered-right-whales-115974">deeply embedded in their flesh</a>, as happened to whale #5120. This can cause infections, chronic emaciation and damage to whales’ blubber, muscle, bone and <a href="https://www.britannica.com/animal/baleen-whale">baleen – the bristly structures in their mouths</a> that they use to filter prey from the water.</p>
<p>North Atlantic right whales are legally protected, both internationally and in U.S. waters, including policies that seek to reduce deaths or serious injuries resulting from entanglements. However, even when entanglement does not kill a whale, it can affect individuals’ ability to reproduce, which is critically important for a species with such low numbers. </p>
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<figcaption><span class="caption">Rescuers successfully remove more than 450 feet (137 meters) of rope and a 135-pound (60-kilogram) trap from an entangled North Atlantic right whale at sea.</span></figcaption>
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<p>In a newly published study, we show that even entanglements scientists classify as minor have <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2024.0314">devastating impacts on female right whales</a> and that, surprisingly, potential mothers who suffer “minor” entanglements have the lowest chance of starting to breed. As researchers with expertise in <a href="https://scholar.google.com.au/citations?user=8zoJjzcAAAAJ&hl=en">marine</a> <a href="https://scholar.google.com/citations?user=8isVxjsAAAAJ&hl=en">biology</a>, <a href="https://scholar.google.com.au/citations?user=CDxPUIEAAAAJ&hl=en">ecology</a> and <a href="https://scholar.google.com/citations?user=P9JQOi8AAAAJ&hl=en">statistics</a>, we believe our findings underline the urgent need for ropeless fishing gear that can reduce threats to the survival of this species.</p>
<h2>Smaller females are having fewer young</h2>
<p>Understanding reproductive patterns is essential for supporting species that are critically endangered. North Atlantic right whales historically started breeding by around 9 years of age and gave birth to a single calf every <a href="https://doi.org/10.3389/fmars.2018.00530">three to four years</a> thereafter for several decades. </p>
<p>Today, however, many females have yet to reproduce at all. Moreover, those that have successfully produced calves now don’t produce another calf for <a href="https://www.narwc.org/uploads/1/1/6/6/116623219/2022reportcardfinal.pdf">more than seven years on average</a>. </p>
<p>As we showed in a 2022 study, after an encouraging North Atlantic right whale population recovery from the 1970s through the early 2000s, the number of reproductively mature female right whales <a href="https://doi.org/10.3389/fmars.2022.994481">declined from 2014 onward</a>. By 2018 there were only about 73 breeding females left, representing roughly half of all females and a sixth of the entire species.</p>
<p>Other research has shown that <a href="https://doi.org/10.3354/meps13299">poor health and physical condition</a> are making it harder for these females to even start breeding. Since the early 1980s, North Atlantic right whales have literally shrunk: Adults have <a href="https://doi.org/10.1016/j.cub.2021.04.067">shorter bodies</a> than they did several decades ago. This trend is associated with entanglements in fishing gear. As is true for all mammals, decreasing female body size <a href="https://doi.org/10.1098/rsos.240050">reduces the likelihood of reproducing</a>. Smaller whales have fewer calves.</p>
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<a href="https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Infographic showing North Atlantic right whale population trends" src="https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581026/original/file-20240311-22-t5wyed.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">North Atlantic right whales have been listed as endangered since 1970. Approximately 360 individuals remain, including around 70 reproductively active females.</span>
<span class="attribution"><a class="source" href="https://www.fisheries.noaa.gov/species/north-atlantic-right-whale">NOAA Fisheries</a></span>
</figcaption>
</figure>
<p>Low calving rates are a <a href="https://www.fisheries.noaa.gov/feature-story/flying-high-save-north-atlantic-right-whales">significant factor in North Atlantic right whales’ decline</a>, so it is important to understand what causes them. Many organizations are involved in <a href="https://whalemap.org/">tracking North Atlantic right whales</a>, including <a href="https://www.fisheries.noaa.gov/species/north-atlantic-right-whale/science">government agencies</a>, <a href="https://www.neaq.org/animal/right-whales/">aquariums</a> and <a href="https://coastalstudies.org/right-whale-research/population-monitoring/">conservation groups</a>. Photos taken from the air enable researchers to identify individuals and so monitor whale population trends, births and deaths, ocean habitat use patterns, health and rates of scarring from entanglements and collisions with ships.</p>
<p>Our new study found that female right whales who have experienced even a minor entanglement before reaching sexual maturity may not ever start to breed. Even females who have previously reproduced are less likely to breed again following an entanglement event.</p>
<p>We determined this by using a mathematical model to incorporate information on the identity of individual whales, derived from photographs of <a href="https://www.neaq.org/conservation-and-research/anderson-cabot-center-for-ocean-life/identifying-right-whales/">natural markings known as callosities</a> on the whales’ heads. By identifying and photographing whales repeatedly over time, scientists can estimate different stages of their life, such as when females give birth. </p>
<h2>Weakness of current regulations</h2>
<p>Researchers categorize the severity of injuries that result from entanglements as <a href="https://doi.org/10.1111/cobi.12590">minor, moderate or severe</a>. The scientists who manage the right whale catalog classify scars or injuries on the skin as minor if they are smaller than 0.8 inches (2 centimeters) without entering the blubber. If they are larger and enter the blubber, they are classified as moderate. Injuries that extend deep into the muscle or bone are categorized as severe.</p>
<p>Our research makes it clear that such value-laden terms are potentially misleading because even minor entanglements can threaten whales’ successful reproduction.</p>
<p>Multiple laws ostensibly protect North Atlantic right whales, including the U.S. <a href="https://www.fisheries.noaa.gov/topic/laws-policies/endangered-species-act">Endangered Species Act</a> and <a href="https://www.fisheries.noaa.gov/topic/laws-policies/marine-mammal-protection-act">Marine Mammal Protection Act</a>, and Canada’s <a href="https://laws-lois.justice.gc.ca/eng/acts/s-15.3/">Species at Risk Act</a>. In our view, these measures do not give enough weight to preventing all types of entanglements, regardless of severity.</p>
<p>Under the Marine Mammal Protection Act, the NOAA develops and implements conservation plans and so-called Take Reduction Plans, which are designed to minimize wildlife deaths and serious injury resulting from commercial fishing gear.</p>
<p>The <a href="https://www.fisheries.noaa.gov/new-england-mid-atlantic/marine-mammal-protection/atlantic-large-whale-take-reduction-plan">Atlantic Large Whale Take Reduction Plan</a>, developed in 1997, requires fishers to use <a href="https://www.fisheries.noaa.gov/new-england-mid-atlantic/marine-mammal-protection/approved-weak-inserts-atlantic-large-whale-take">weak links</a>, with a maximum breaking strength of 1,700 pounds (771 kilograms), to connect lobster and crab pots to buoys on the surface. These links are intended to break when whales swim into them, so that the whales do not become entangled and weighted down by ropes and traps. </p>
<p>The plan also requires fishers to use heavy ground lines to connect multiple traps or pots. These lines are designed to sink to the bottom rather than floating in the water column. And the plan closes trap fishing areas seasonally when whales are known to be present in those zones. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OGBjNL-8ac0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">U.S. and Canadian regulators are considering requiring ‘ropeless’ lobster and crab fishing gear in zones where right whales are present.</span></figcaption>
</figure>
<h2>Coming back from the brink</h2>
<p>Current population estimates suggest that the numbers of North Atlantic right whales <a href="https://www.neaq.org/right-whale-population-estimates-indicate-slowing-decline-scientists-highlight-threats-to-species/">could be stabilizing</a>, meaning that the number of deaths is approximately equal to the number being born. While these estimates seem promising, females need to start and continue producing calves to increase whales’ numbers. </p>
<p>From our work, it is very clear that both lethal and sublethal impacts of entanglements are of grave concern for these whales. As we see it, eliminating entanglement, not mitigating it, is the only way to avoid the extinction of this species. Every entanglement, whatever its severity, is bad news for the whales.</p><img src="https://counter.theconversation.com/content/225257/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Leslie New receives funding from the U.S. Office of Naval Research and the National Science Foundation. She also is a member of the International Whaling Commission Scientific Committee.</span></em></p><p class="fine-print"><em><span>Peter Corkeron consults for Public Employees for Environmental Responsibility on right whale conservation issues. He headed the National Oceanic and Atmospheric Administration's large whale research program for the northeastern US from 2011 to 2019, then led the New England Aquarium's right whale research program through 2022.</span></em></p><p class="fine-print"><em><span>Rob Harcourt receives funding from the Australian Federal Government Department of Climate Change, Environment, Energy and Water for research on right whales. He was a member of the National Marine Mammal Scientific Committee </span></em></p><p class="fine-print"><em><span>Joshua Reed does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Even when female North Atlantic right whales survive entanglement in fishing gear, it may affect their future ability to breed, increasing the pressure on this critically endangered species.Joshua Reed, Research Associate in Biology, Macquarie UniversityLeslie New, Assistant Professor of Statistics, Ursinus CollegePeter Corkeron, Adjunct Senior Research Fellow, Centre for Planetary Health and Food Security, Griffith UniversityRob Harcourt, Professor of Marine Ecology, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2246072024-03-06T19:07:52Z2024-03-06T19:07:52ZSharks, turtles and other sea creatures face greater risk from industrial fishing than previously thought − we estimated added pressure from ‘dark’ fishing vessels<figure><img src="https://images.theconversation.com/files/580177/original/file-20240306-22-3smwaf.jpg?ixlib=rb-1.1.0&rect=17%2C0%2C2977%2C1998&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Seabirds like this sooty shearwater can drown when they become tangled in drift nets and other fishing gear. </span> <span class="attribution"><a class="source" href="https://flic.kr/p/dj3H6v"> Roy Lowe, USFWS/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>My colleagues and I mapped activity in the northeast Pacific of “dark” fishing vessels – boats that turn off their location devices or lose signal for technical reasons. In <a href="https://www.science.org/doi/10.1126/sciadv.adl5528">our new study</a>, we found that highly mobile marine predators, such as sea lions, sharks and leatherback sea turtles, are significantly <a href="https://news.stanford.edu/2019/03/13/tunas-sharks-ships-sea/">more threatened than previously thought</a> because of large numbers of dark fishing vessels operating where these species live. </p>
<p>While we couldn’t directly watch the activities of each of these dark vessels, <a href="https://www.theguardian.com/environment/2022/nov/02/at-least-6-percent-global-fishing-likely-as-ships-turn-off-tracking-devices-study">new technological advances</a>, including satellite data and machine learning, make it possible to estimate where they go when they are not broadcasting their locations. </p>
<p>Examining five years of data from fishing vessel location devices and the habitats of 14 large marine species, including seabirds, sharks, turtles, sea lions and tunas, we found that our estimates of risk to these animals increased by nearly 25% when we accounted for the presence of dark vessels. For some individual predators, such as albacore and bluefin tunas, this adjustment increased risk by over 36%. The main hot spots were in the Bering Sea and along the Pacific coast of North America. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bjFSgr_B38I?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Bycatch, or accidental take, is the leading threat to some endangered marine species.</span></figcaption>
</figure>
<h2>How we did our work</h2>
<p>Fishing boats use <a href="https://globalfishingwatch.org/faqs/what-is-ais/">Automatic Identification System</a>, or AIS, to avoid colliding with each other. Their AIS signals bounce off satellites to reach nearby ships. </p>
<p>This data is a valuable tool for <a href="https://www.cbsnews.com/detroit/news/study-choosing-fish-may-be-killing-sharks/">mapping risk at sea</a> and <a href="https://www.bbc.com/news/science-environment-43169824">understanding the footprints of fishing fleets</a>. AIS data captures an estimated <a href="http://dx.doi.org/10.1126/science.aao564">50% to 80%</a> of fishing operations occurring more than 100 nautical miles from shore.</p>
<p>But in some areas, vessels’ AIS signals can’t reach the satellites, either because reception is poor or many boats are crowded together – much as cellphones can have difficulty sending text messages in remote wildness or in crowded stadiums. And just as location tracking can be disabled on phones, fishing vessels can intentionally <a href="https://theconversation.com/when-fishing-boats-go-dark-at-sea-theyre-often-committing-crimes-we-mapped-where-it-happens-196694">disable their AIS</a> if they want to hide their location. Boats that do this may be engaged in criminal activities, such as <a href="https://www.penguinrandomhouse.com/books/538736/the-outlaw-ocean-by-ian-urbina/">illegal fishing or human trafficking</a>.</p>
<p>We calculated how much risk dark vessels pose to marine life by overlapping their activity with the modeled habitats of 14 highly mobile marine predators. Using the same method, we also calculated how much risk observable fishing vessels that broadcast their locations pose to marine life. These two calculations allowed us to understand the additional risk from dark fishing vessels.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A seal on a beach, with a rope wrapped around it and connected to a large orange float beside the animal." src="https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/579990/original/file-20240305-26-vf2vcl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A Hawaiian monk seal entangled on a large fishing float.</span>
<span class="attribution"><a class="source" href="https://photolib.noaa.gov/Collections/Fisheries/Other/emodule/1054/eitem/61324">Doug Helton, NOAA/NOS/ORR/ERD</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Why it matters</h2>
<p>We know that many sea creatures, including endangered species, are <a href="https://www.msc.org/en-us/what-we-are-doing/oceans-at-risk/overfishing">killed by overfishing</a>, <a href="https://www.latimes.com/opinion/op-ed/la-oe-welch-sea-turtles-swordfish-climate-change-20190610-story.html">accidental catch</a> and <a href="https://www.fisheries.noaa.gov/west-coast/marine-mammal-protection/west-coast-large-whale-entanglement-response-program">entanglement in fishing gear</a>. More overlap between wildlife and fishing boats means that those harmful impacts are more likely to happen. </p>
<p>Even considering only <a href="https://globalfishingwatch.org/map/index?start=2023-11-25T00%3A00%3A00.000Z&end=2024-02-25T00%3A00%3A00.000Z&latitude=19&longitude=26&zoom=1.5">observable fishing boats broadcasting their positions</a>, the presence of boats signals considerable risk for marine life. For example, <a href="https://www.fisheries.noaa.gov/species/california-sea-lion">California sea lions</a> forage in Pacific coastal waters from the Canadian border to Baja California and are accidentally caught by boats fishing for hake and halibut. We found observable fishing activity in over 45% of the sea lions’ habitat. </p>
<p>In another example, migratory <a href="https://www.adfg.alaska.gov/index.cfm?adfg=salmonshark.main">salmon sharks</a> feed on salmon near Alaska’s Aleutian Islands during the summer and breed in warmer waters off the coasts of Oregon and California during the winter. Along their journey, salmon sharks are accidentally caught in fishing nets and longlines. We detected observable vessel fishing activity in nearly one-third of salmon shark habitat. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&rect=31%2C0%2C5169%2C3461&q=45&auto=format&w=1000&fit=clip"><img alt="Dozens of fishing boats move out of an urban harbor" src="https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&rect=31%2C0%2C5169%2C3461&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/579983/original/file-20240305-28-en5un3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fishing boats head out for the East China Sea in Zhoushan, Zhejiang Province, China.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/fishing-boats-set-sail-in-the-morning-to-east-china-sea-for-news-photo/1340823231">Shen Lei/VCG via Getty Images</a></span>
</figcaption>
</figure>
<p>Our findings indicate that such threats are higher when dark fishing boats are present. Estimates of risk to California sea lions and salmon sharks increased by 28% and 23%, respectively, when we accounted for dark vessels.</p>
<p>This information could affect fishery regulation. For example, regulators <a href="https://www.fisheries.noaa.gov/feature-story/fish-stock-assessment-101-part-2-closer-look-stock-assessment-models">use risk information</a> to set catch limits for species such as tuna; higher risk could mean that catch limits need to be lower. </p>
<p>For species such as sea lions and salmon sharks that are accidentally caught by fishermen, higher risk levels could indicate that fishing boats should use more selective gear. California is currently acting on this issue by helping fishermen phase out use of <a href="https://opc.ca.gov/2022/11/phase-out-drift-gillnets/">large-mesh drift gill nets</a> in state waters. These nets, which hang like curtains in the water, catch <a href="https://www.fao.org/3/T0502E/T0502E01.htm">many other fishes along with the target species</a>. </p>
<p>Accounting for dark vessels is particularly important in international waters where boats from multiple countries operate, because AIS data is one of the most complete sources of fishing activity across nations. Tracking dark vessels can help make this information as comprehensive as possible and provide insights into the multinational impacts of fishing. </p>
<p>Our study does not account for vessels that do not use any vessel tracking system, or that use systems other than AIS. Therefore, our risk calculations likely still underestimate the true impact of fisheries on marine predators. </p>
<h2>What’s next</h2>
<p>The world’s oceans are rich in life but poor in data, although this is changing. High-resolution <a href="https://www.smithsonianmag.com/smart-news/satellite-maps-reveal-rampant-fishing-untracked-dark-vessels-oceans-180983539/">satellite imagery</a> may soon offer even more information on risk from dark vessels. </p>
<p>President Joe Biden and other global leaders have pledged to protect <a href="https://www.whitehouse.gov/briefing-room/statements-releases/2023/03/21/fact-sheet-biden-harris-administration-takes-new-action-to-conserve-and-restore-americas-lands-and-waters/">30% of the ocean by 2030</a>. Better data on human-wildlife interactions at sea can help ensure that new protected areas are in the right places to make a difference.</p><img src="https://counter.theconversation.com/content/224607/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Heather Welch receives funding from NOAA's Office of Law Enforcement. </span></em></p>The toll on wildlife from illegal fishing, bycatch and entanglement in fishing gear is likely underestimated, because it doesn’t account for ‘dark’ fishing vessels, a new study finds.Heather Welch, Researcher in Ecosystem Dynamics, University of California, Santa CruzLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2242422024-03-04T01:46:59Z2024-03-04T01:46:59ZYabby traps and discarded fishing tackle can kill platypuses - it’s time to clean up our act<figure><img src="https://images.theconversation.com/files/579434/original/file-20240303-16-g8s75y.jpg?ixlib=rb-1.1.0&rect=33%2C4%2C3161%2C2122&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/platypus-wild-australia-1422117959">Mari_May, Shutterstock</a></span></figcaption></figure><p><a href="https://www.agriculture.gov.au/agriculture-land/fisheries/recreational">Recreational fishing</a> is a popular pastime in Australia’s inland rivers and streams. Unfortunately in the process, many people are unwittingly killing platypuses. </p>
<p>The animals can become trapped in nets commonly used to catch yabbies such as “<a href="https://kb.rspca.org.au/knowledge-base/can-enclosed-yabby-traps-harm-animals-and-are-they-legal-to-use/">Opera House traps</a>” (so-called because their shape resembles the sails of the Sydney Opera House). The enclosed structure stops platypuses swimming back to the surface to breathe, causing them to drown in minutes.</p>
<p>Enclosed traps are banned in most states, but they are <a href="https://kb.rspca.org.au/knowledge-base/can-enclosed-yabby-traps-harm-animals-and-are-they-legal-to-use/">still being used</a>. They are sold online and can be shippped across Australia. During our field research, we frequently encounter these traps and clumps of discarded fishing line. We have also conducted research on the bodies of platypuses killed by these hazards.</p>
<p>It’s time for a national ban on these inhumane traps. And recreational fishing waste should be kept out of our waterways. We must save our platypuses, before it’s too late. </p>
<figure>
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<figcaption><span class="caption">Platypuses being released back into the Hawkesbury-Nepean River catchment, New South Wales.</span></figcaption>
</figure>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/even-platypuses-arent-safe-from-bushfires-a-new-dna-study-tracks-their-disappearance-212651">Even platypuses aren't safe from bushfires – a new DNA study tracks their disappearance</a>
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<h2>A natural wonder</h2>
<p>The <a href="https://australian.museum/learn/animals/mammals/platypus/">platypus</a> is one of Australia’s most loved and iconic species. These semi-aquatic, air breathing monotremes (egg-laying mammals) can be naturally found in waterways of the east coast, Tasmania and Kangaroo Island. </p>
<p>But there are <a href="https://www.sciencedirect.com/science/article/pii/S2351989419302276">growing concerns for the species’ survival</a>. Platypuses are becoming scarce and in some areas, completely disappearing from waterways.</p>
<p>The animals spend most of their time foraging in freshwater creeks and rivers. They have very poor eyesight underwater and use special sensors in their duck-shaped bill to locate prey. A trap full of live yabbies can attract platypuses, but this tempting feast may be their last meal.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-platypus-can-glow-green-and-hunt-prey-with-electricity-but-it-cant-climb-dams-to-find-a-mate-193707">A platypus can glow green and hunt prey with electricity – but it can't climb dams to find a mate</a>
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<h2>Closing in on enclosed traps</h2>
<p>Closed-top traps are baited then submerged in a river or stream for hours or a day, before being hauled out. </p>
<p>The traps funnel creatures into an enclosed space where they can’t escape. They are designed to catch freshwater crayfish (known as yabbies or marron). But they also inadvertently trap aquatic animals such as platypuses, freshwater turtles and the native water rat, rakali. </p>
<p>But there are wildlife-friendly alternatives. For example, some nets are <a href="https://www.bcf.com.au/p/wilson-yabby-mesh-drop-pot-1in/M156393.html?cgid=species-yabbies#start=3">open</a> at the top while others have a hinged lid that can be pushed open by a larger animal, such as a platypus, as it tries to escape. </p>
<p>Opera House style, closed-top yabby traps are now <a href="https://www.ifs.tas.gov.au/the-rules/allowed-angling-methods#:%7E:text=You%20cannot%20possess%20or%20use,including%20platypus%20and%20water%20rats.">banned in Tasmania</a>, <a href="https://vfa.vic.gov.au/recreational-fishing/fisheries-management/changes-ahead-for-yabby-fishing-gear">Victoria</a>, the <a href="https://www.cmtedd.act.gov.au/open_government/inform/act_government_media_releases/gentleman/2019/cruel-nets-banned-in-all-act-waters">Australian Capital Territory</a>, <a href="https://www.dpi.nsw.gov.au/about-us/media-centre/releases/2021/reminder-new-yabby-net-rules-are-now-in-place">New South Wales</a> and <a href="https://pir.sa.gov.au/alerts_news_events/news/fishing_and_aquaculture/opera_house_yabby_nets_banned">South Australia</a>. </p>
<p><a href="https://www.qld.gov.au/recreation/activities/boating-fishing/rec-fishing/rules/equipment">Queensland allows use</a> west of the Dividing Range, where platypuses are not thought to exist, or on private property. Restrictions around the <a href="https://wildlife.org.au/our-work/advocacy-campaigns/ban-opera-house-nets/">size of trap entrance holes</a> were introduced in 2015.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An abandoned opera house trap on the banks of a creek in the southern highlands of NSW" src="https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578787/original/file-20240228-28-3xjoe8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An abandoned opera house trap in known platypus territory, a creek in the Southern Highlands, NSW.</span>
<span class="attribution"><span class="source">Katherine Warwick</span></span>
</figcaption>
</figure>
<h2>A litany of platypus deaths</h2>
<p>The Australian Platypus Conservancy found <a href="https://biostor.org/reference/236537">41% of reported platypus deaths</a> from 1980 to 2009 were caused by drowning in enclosed nets. </p>
<p>Meanwhile platypuses have continued to drown in closed-top traps. In 2022, <a href="https://www.abc.net.au/news/2022-05-25/platypus-yabby-trap-deaths/101095130">four reportedly died</a> in one trap at Dorrigo on the mid-north coast of New South Wales. In 2021, a platypus <a href="https://www.abc.net.au/news/2021-05-05/hunt-for-those-responsible-for-platypus-death/100114874">died in Queensland’s Broken River</a> and in 2018, one trap <a href="https://wyndham.starweekly.com.au/news/platypuses-found-dead-in-illegal-net-in-werribee-river/">drowned seven</a> in Victoria’s Werribee River.</p>
<p>Aside from deaths by closed-top traps, many platypuses become entangled in abandoned fishing line as they search for food along the bottom of waterways. </p>
<p>The animal’s tapered shape, duck-shaped bill and short webbed feet make it hard to free themselves. They are prone to getting wrapped in rings or loops of plastic, rubber or metal rubbish. </p>
<p>In 2021 a Victorian study of <a href="https://www.publish.csiro.au/am/am21004">54 cases of platypus entanglement</a> found litter commonly encircled the neck (68%). Almost one in five were wrapped “from in front of a shoulder to behind the opposite foreleg” (22%). Others had plastic around their torso or jaw.</p>
<p>That study also found platypuses in greater Melbourne were up to eight times more likely to become tangled in litter than those in regional Victoria. That’s because urban areas tend to be more polluted. </p>
<p>Fishing line can cut through skin and muscle, causing a slow painful death. Entangled platypuses can also drown after they become caught on underwater debris.</p>
<p>We study how heavy metals and other emerging contaminants accumulate in platypuses. Together with the community, local and state governments and wildlife organisations such as Taronga Zoo, we collect dead platypuses to examine their organs and body tissues. </p>
<p>On a trip this month to regional NSW for water quality testing and sampling, we found multiple instances of tangled fishing line and an abandoned submerged Opera House trap. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578096/original/file-20240226-18-fe89vv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A dead platypus entangled in fishing line, found in the Southern Highlands of NSW.</span>
<span class="attribution"><span class="source">Katherine Warwick</span></span>
</figcaption>
</figure>
<h2>Swapping traps and binning trash</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="One of the TAngler bins for used fishing line on the banks of the Hawkesbury-Nepean River, which looks like a PVC pipe periscope strapped to a post" src="https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=899&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=899&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=899&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578431/original/file-20240227-30-gmllrf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">TAngler bins are available for the safe disposal of used fishing line on the banks of the the Hawkesbury-Nepean River, NSW.</span>
<span class="attribution"><span class="source">Michelle Ryan</span></span>
</figcaption>
</figure>
<p>Between December 2018 and February 2019, when the Victorian Fisheries Authority invited people to swap their old closed top nets for a free “wildlife friendly” net, <a href="https://vfa.vic.gov.au/recreational-fishing/fisheries-management/changes-ahead-for-yabby-fishing-gear">20,000 traps were exchanged</a>. </p>
<p>OzFish and Ocean Earth Foundation are currently running a <a href="https://ozfish.org.au/projects/yabby-trap-round-up/">Yabby Trap Round Up</a> in NSW and SA. The Opera House traps are recycled and turned into useful fishing products. </p>
<p>Recreational fishers should also round up their used fishing line and hooks. The “<a href="https://www.oceanwatch.org.au/tangler-bins/">TAngler bin</a>” initiative encourages safe disposal. Since 2006, more than 350 TAngler bins have been installed at fishing hotspots in Victoria, NSW and Queensland, collecting more than ten tonnes of discarded fishing line. </p>
<p>A study in known platypus habitat on the Hawkesbury-Nepean River in Greater Sydney found <a href="https://www.westernsydney.edu.au/newscentre/news_centre/story_archive/2019/western_researchers_tackle_fishing_line_waste_in_the_hawkesbury">more than 2.5km of fishing line was disposed of correctly</a> in the bins in just three years.</p>
<h2>Save our platypuses</h2>
<p>Closed-top nets should be banned nationwide. This would ensure recreational fishers can no longer buy these traps and then use them in banned areas, as is happening now. </p>
<p>Net exchange programs should continue, in conjunction with a national awareness campaign, so the closed-top traps already sold are all handed in. </p>
<p>And both fishers and the wider community can take action by collecting discarded fishing line and nets. </p>
<p>Platypuses need all the help they can get. With our support, these beloved iconic animals can live on in Australian waterways. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/our-native-animals-are-easy-prey-after-a-fire-could-artificial-refuges-save-them-223357">Our native animals are easy prey after a fire. Could artificial refuges save them?</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/224242/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Katherine Warwick has received funding from industry, community groups, not-for-profit organisations, Commonwealth, New South Wales and local Government. She has previously worked for Blue Mountains City Council.</span></em></p><p class="fine-print"><em><span>Ian Wright has received funding from industry, Commonwealth, NSW and local Government. He has previously worked for Sydney Water. </span></em></p><p class="fine-print"><em><span>Michelle Ryan receives funding from industry, community groups, not for profit organisations as well as Commonwealth, NSW and local Government.
</span></em></p>Platypuses are drowning in Australian waterways, tangled in fishing line and trapped in closed nets meant for freshwater crayfish or yabbies. But we can fix this.Katherine Warwick, PhD Candidate, Western Sydney UniversityIan A. Wright, Associate Professor in Environmental Science, Western Sydney UniversityMichelle Ryan, Senior lecturer, Western Sydney UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2233052024-03-01T02:15:13Z2024-03-01T02:15:13ZOn fisheries, Australia must be prepared for New Zealand as opponent rather than ally<figure><img src="https://images.theconversation.com/files/578815/original/file-20240229-26-3xjoe8.jpg?ixlib=rb-1.1.0&rect=6%2C0%2C4403%2C2942&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fishing-net-trawler-hauled-on-deck-2146555375">Tara Lambourne/Shutterstock</a></span></figcaption></figure><p>On February 1, senior Australian and New Zealand ministers signed a <a href="https://www.foreignminister.gov.au/minister/penny-wong/media-release/joint-statement-australia-new-zealand-ministerial-consultations-anzmin-2024">Joint Statement of Cooperation</a>, acknowledging the long history of collaboration between the two nations. </p>
<p>The same week, New Zealand <a href="https://www.sprfmo.int/assets/Meetings/01-COMM/12th-Commission-2024/COMM12-Report-2024-Final-26Feb24-No-Annexes.pdf">rejected</a> an Australian proposal on sustainable fishing at the annual fisheries meeting of nations that fish in the high seas of the South Pacific. The move has driven a wedge between these traditional allies. </p>
<p>At stake was an agreement by those nations to protect 70% of special and vulnerable marine ecosystems, such as ancient corals, from destructive fishing practices like bottom-trawling. </p>
<p>Until December 2023, NZ was jointly leading the work to implement this agreement with Australia. But New Zealand’s new government, a coalition of conservative parties, rejected the proposed restrictions, citing concerns about jobs and development. </p>
<p>This sudden about-face raises many questions for Australia, and for progress on sustainable fishing more generally. On fishing, Australia must now be prepared to consider New Zealand an opponent rather than ally. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1761828748163420434"}"></div></p>
<h2>Sustainable fishing alliance no more?</h2>
<p>In 2009, Australia, New Zealand and Chile led successful negotiations for a convention governing sustainable fishing in the South Pacific high seas beyond a nation’s marine exclusive economic zones, meaning more than 370km off the coast. The goal was to make sure fish stocks were not fished out and to protect marine ecosystems. (Tuna are not included, as they are dealt with under a separate convention.) </p>
<p>Since then, New Zealand and Australia have led much of the development of regulations governing the sustainable use of deepwater fish species and the conservation of vulnerable marine ecosystems in the South Pacific region. Their work led to the first measures governing deepwater fisheries, science-based catch limits for deepwater species, and a joint assessment of seafloor fishing methods such as trawling.</p>
<p>But the idea of banning or restricting trawling was controversial. Bottom-trawling, in which boats deploy giant nets that scrape along the ocean floor, is very effective – so much so that it can devastate everything in its path. </p>
<p>In 2015, the United Nations’ first <a href="https://www.un.org/regularprocess/content/first-world-ocean-assessment#:%7E:text=The%20First%20Global%20Integrated%20Marine,Marine%20Environment%2C%20including%20Socioeconomic%20Aspects">worldwide ocean assessment</a> found bottom-trawling causes widespread, long-term destruction to deep-sea environments wherever it is done. Scientists have compared it to clear-felling a forest. The practice is banned in the Mediterranean and in shallow waters of the Southern Ocean, and is increasingly restricted by many nations, including Australia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="bottom trawling coral" src="https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/580023/original/file-20240305-16-hv069o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This 2005 photo shows crew on the New Zealand bottom trawler, Waipori, dumping a large piece of Paragorgia coral dredged from the deep sea in their net.</span>
<span class="attribution"><a class="source" href="https://www.greenpeace.org/aotearoa/story/writing-on-the-wall-for-nz-bottom-trawling-industry/">Malcolm Pullman/Greenpeace</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>The UN has repeatedly called for better protection, as well as specific actions to make it a reality. And many nations and organisations are heeding that call. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-now-have-a-treaty-governing-the-high-seas-can-it-protect-the-wild-west-of-the-oceans-201184">We now have a treaty governing the high seas. Can it protect the Wild West of the oceans?</a>
</strong>
</em>
</p>
<hr>
<p>The science is clear. But the politics is not. International waters in the South Pacific are one of the few areas where deepwater bottom-trawling is still permitted on seamounts – underwater mountains rich in life – and similar features.</p>
<p>Last year, South Pacific nations agreed to protect a minimum of 70% of marine ecosystems vulnerable to damage from fishing. This agreement came from research done largely by New Zealand. </p>
<p>Other countries pushed for a higher level of protection, but New Zealand insisted on 70% to ensure its fishing could continue. These kinds of compromises are common at meetings like this.</p>
<p>The meeting in February was meant to agree on how to make the consensus decision a reality. But it was not to be. Now that NZ has withdrawn support, the original decision remains but without the mechanisms to make it happen. Bottom-trawling will likely continue in the South Pacific. </p>
<p>Why? The new NZ fisheries minister, Shane Jones, has <a href="https://newsroom.co.nz/2024/02/01/jones-to-make-nz-jobs-no-1-to-dismay-of-ocean-conservation-allies/">publicly stated</a> he was “keen to ensure that, number one, we’re looking after our own people, looking after jobs and opportunities for economic development to benefit New Zealand.”</p>
<p>While high seas fishing is an important industry for New Zealand, their bottom trawling activity in the South Pacific <a href="https://www.sprfmo.int/assets/Meetings/02-SC/11th-SC-2023/Plenary-documents/SC11-Doc16-Annual-Report-of-New-Zealand-to-SC11-2023.pdf">is small</a>. One vessel fished the bottom in 2021-2022, catching only 20 tonnes of orange roughy. No bottom trawling has happened since then. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="fishing boats in Auckland" src="https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578819/original/file-20240229-28-1xzxwv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">New Zealand’s seafood exports are economically important.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/auckland-new-zealand-february-01-2016-381601837">krug_100/Shutterstock</a></span>
</figcaption>
</figure>
<p>Since coming to power, New Zealand’s new government has questioned 2030 renewable energy targets, promised to “address climate change hysteria”, declared mining more important than nature protection – and supported bottom-trawling. </p>
<p>Many of these changes will be of considerable concern to Australia. For the past 15 years, Australia has taken a prominent leadership role – alongside New Zealand – in sustainable ocean management. </p>
<p>With Pacific island nations, Australia and NZ worked long and hard to progress the High Seas Treaty – a breakthrough <a href="https://theconversation.com/we-now-have-a-treaty-governing-the-high-seas-can-it-protect-the-wild-west-of-the-oceans-201184">opening new legal avenues</a> to protect up to 30% of the unregulated high seas where illegal and exploitative fishing practices are common. </p>
<p>The NZ government’s willingness to jettison long collaborative work, abandon agreed commitments and risk existing agreements bodes poorly for cooperation across the Tasman. Australia must sadly now treat New Zealand as an opponent when it comes to protecting the seas and managing fisheries for the long term. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/we-now-have-a-treaty-governing-the-high-seas-can-it-protect-the-wild-west-of-the-oceans-201184">We now have a treaty governing the high seas. Can it protect the Wild West of the oceans?</a>
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<img src="https://counter.theconversation.com/content/223305/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lynda Goldsworthy has attended South Pacific regional fisheries meetings as an academic advisor on the Australian delegation for the past 5 years, and provides occasional consultancy advice to the Deep Sea Conservation Coalition on high seas conservation issues. </span></em></p>For years, Australia and New Zealand have been united in working for sustainable fishing in the South Pacific. That just changed.Lynda Goldsworthy, Research Associate, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2189772024-02-15T22:07:25Z2024-02-15T22:07:25Z8 ways that stopping overfishing will promote biodiversity and help address climate change<figure><img src="https://images.theconversation.com/files/576010/original/file-20240215-18-gqysb.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3804%2C2545&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Schools of jackfish pictured in the ocean off Losin, Thailand. Overfishing is a contributing factor in global climate change.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Amid the escalating threats of a warming world, and with the latest annual United Nations global climate conference (COP28) behind us, there is one critical message that’s often left out of the climate change discourse. Halting overfishing is itself effective climate action.</p>
<p>This argument is the logical conclusion of a plethora of studies that unequivocally assert that stopping overfishing isn’t just a necessity, it’s a win-win for ocean vitality, climate robustness and the livelihoods reliant on sustainable fisheries.</p>
<p>The intricate relationship between climate change and ocean ecosystems was the subject of recent collaborative research — led by researchers at the University of British Columbia — that highlighted the crucial links between overfishing and climate change. </p>
<h2>Finding the connections</h2>
<p>Our collaborative team of international researchers applied a host of methodologies ranging from literature reviews to quantitative and quality analysis. The findings of <a href="https://doi.org/10.3389/fmars.2023.1250449">this research</a> illuminate eight key multifaceted impacts.</p>
<p>1 — Ending overfishing <a href="https://doi.org/10.3389/fmars.2020.00523">isn’t merely an ecological imperative but a vital climate action</a>. Doing so would bolster marine life resilience in the face of climate shifts and reduce associate carbon emissions.</p>
<p>2 — Large subsidized fishing boat fleets can <a href="https://doi.org/10.1126/science.abm1680">actually be a burden on small-scale fisheries, leaving them disproportionately vulnerable to shocks</a>. In turn, overfishing not only depletes resources but also escalates carbon emissions, <a href="https://doi.org/10.3389/fmars.2022.768784">intensifying climate impacts on these fisheries and their communities, particularly women</a>.</p>
<p>Additionally, the <a href="https://doi.org/10.3389/fmars.2022.802762">vulnerability of shellfish fisheries to climate stressors further underscores the importance of adaptive strategies</a> tailored to local conditions. </p>
<p>3 — Success stories, like the recovery of European hake stocks, <a href="https://doi.org/10.3389/fmars.2022.788339">reveal a direct tie between stock recuperation and reduced emissions intensity from fisheries</a>. <a href="https://theconversation.com/how-to-stay-hopeful-in-a-world-seemingly-beyond-saving-210415">We must champion and also learn from these successes</a>.</p>
<p>4 — Ecosystem-based fisheries management reverses the “order of priorities so that management starts with ecosystem considerations rather than the maximum exploitation of several target species.” </p>
<p>Ecosystem-based fisheries management has considerable potential to enhance sustainable catches while fostering carbon sequestration. This is perhaps <a href="https://doi.org/10.3389/fmars.2022.879998">best exemplified by the successful implimentation of ecosystem-based fisheries management in the western Baltic Sea</a>.</p>
<p>5 — <a href="https://doi.org/10.3389/fmars.2021.770805">Heavy metal pollution in the ocean — such as mercury or lead waste — intensifies the negative impacts of warming and overfishing</a>. This pollution reinforces the need for developing multifaceted regulations based around ecosystem and ocean sustainability solutions. </p>
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Read more:
<a href="https://theconversation.com/flipping-indigenous-regional-development-in-newfoundland-upside-down-lessons-from-australia-218298">Flipping Indigenous regional development in Newfoundland upside-down: lessons from Australia</a>
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<p>6 — Overfishing <a href="https://doi.org/10.3389/fmars.2021.597385">exacerbates climate and biodiversity threats</a>. Climate change contributes to less defined and predictable seasons <a href="https://theconversation.com/how-climate-change-induced-stress-is-altering-fish-hormones-with-huge-repercussions-for-reproduction-213140">and is causing reproductive challenges</a> and the <a href="https://theconversation.com/climate-change-is-further-reducing-fish-stocks-with-worrisome-implications-for-global-food-supplies-217428">propagation of diseases in fish populations</a> — among other issues.</p>
<p>Adding to these problems, <a href="https://doi.org/10.1016/j.tree.2007.07.001">overfishing itself is altering ecological dynamics, modifying habitats and opening new pathways for invasive species</a>. These compounding crises further exacerbate the impacts of overfishing on marine ecosystems while at the same time making fish populations more vulnerable to climate change.</p>
<p>The above factors all combine to reduce the catch potential in any given ecosystem. In turn, fishers are forced to venture farther and deeper in the ocean to fish — increasing carbon emissions, personal risk factors to fishers and <a href="https://www.greenmatters.com/p/what-is-bycatch">bycatch</a> concerns. </p>
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<img alt="A dead shark is seen tangled in a fishing net." src="https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=386&fit=crop&dpr=1 600w, https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=386&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=386&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=485&fit=crop&dpr=1 754w, https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=485&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/576013/original/file-20240215-24-d1h82g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=485&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Reduced fish catches can lead to fishers going farther, and deeper, out to sea to find fish — with a host of associated consequences.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>7 — International fisheries management must play a central role in promoting biodiversity and retaining the ocean’s carbon sequestration potential. While 87 nations have signed the UN’s <a href="https://doi.org/10.3389/fmars.2022.764609">Biodiversity of Areas Beyond National Jurisdiction Treaty</a> (also known as the High Seas Treaty), only one has ratified it. This treaty must be fully ratified and its effective implementation should be contingent upon the creation of marine protected areas that cover at least 30 per cent of the high seas.</p>
<p>8 — The ocean has huge carbon sequestration potential. <a href="https://doi.org/10.3389/fmars.2022.800972">Shifting from the generally accepted maximum of sustainable yield management to maximizing carbon sequestration in fisheries management could further advance climate goals</a>.</p>
<p>Future regulations should allocate a percentage of the annual fish quota to maintain the carbon sequestration function of marine animals. Simply put, beyond just being food, fish stocks serve vital carbon sequestration and biodiversity services that directly benefit humanity. Future regulations should reflect this reality.</p>
<h2>A simple goal</h2>
<p>This joint collaborative research underscores the urgency of this issue. Ending overfishing isn’t just an ecological imperative but a linchpin for climate action. Furthermore, fisheries aren’t mere victims in these dynamics, but have real agency to play a pivotal role in either exacerbating or mitigating climate change.</p>
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<p>An ideal governance framework would focus on managing ecosystems with considerations for their diverse benefits, based on the best evidence available. Regulation of fisheries, while controversial, is essential to not overly exploit such a valuable public resource.</p>
<p>As we gear up to the next COP, we would do well to remember these conclusions. Without nurturing ocean life, addressing climate change becomes an uphill battle. Sustainable fisheries management is not just an ecological necessity. It is also the cornerstone of a resilient, sustainable future.</p><img src="https://counter.theconversation.com/content/218977/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rashid Sumaila receives funding from the Social Sciences and Humanities Research Council and the non-governmental organization Our Fish.</span></em></p>Recent research shows how reducing overfishing is both an ecological imperative and a critical means to addressing climate change.Rashid Sumaila, Director & Professor, Fisheries Economics Research Unit, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2231712024-02-13T12:45:10Z2024-02-13T12:45:10ZStruggling seabirds thrown a lifeline by new commercial fishing ban in the North Sea – but it may not be enough<figure><img src="https://images.theconversation.com/files/574500/original/file-20240208-20-wgkkts.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Puffins and many other seabirds rely on sandeels as a food source. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/closeup-atlantic-puffin-fish-beak-1909632901">Arnoud Quanjer/Shutterstock</a></span></figcaption></figure><p>With their bright, orange feet and colourful beaks full of glistening fish, puffins are really charismatic seabirds. But <a href="https://jncc.gov.uk/our-work/seabirds-count/#results">puffin populations are in decline</a>, largely due to their struggle to catch enough of <a href="https://datazone.birdlife.org/species/factsheet/atlantic-puffin-fratercula-arctica/details">these shiny fish: sandeels</a>. </p>
<p>Sandeels have been industrially fished on an industrial scale <a href="https://academic.oup.com/icesjms/article/59/2/261/619635">since the 1950s</a>, not for human consumption but to make fishmeal. They are the bedrock of marine ecosystems in the <a href="https://consult.defra.gov.uk/wg-management-measures-for-industrial-sandeel-fishing/consultation-on-spatial-management-measures-for-in/supporting_documents/What%20are%20the%20ecosystem%20risks%20and%20benefits%20of%20full%20prohibition%20of%20industrial%20Sandeel%20fishing%20in%20the%20UK%20waters%20of%20the%20North%20Sea%20ICES%20Area%20IV.pdf">North Sea</a>. But a new fishing ban could provide welcome respite for puffins and other marine wildlife. </p>
<p>The UK and Scottish governments have announced a permanent end to industrial sandeel fishing in English and Scottish waters. <a href="https://blogs.gov.scot/marine-scotland/2024/01/31/sandeel-fishing-to-be-banned-in-scottish-waters/">This ban</a> will begin on April 1 – the start of this year’s sandeel fishing season. </p>
<p>The news of the closure of this sandeel fishery has been met with praise from across the conservation sector. A quarter of a century of <a href="https://www.rspb.org.uk/whats-happening/news/sandeel-campaign-success-in-england">campaigning by the RSPB</a> seems to have paid off. </p>
<p>The health of sandeel populations in Scottish and English seas can link to the breeding success of the seabirds that feed on them, but the correlation is complex. This fishing ban is a start but, with the added pressures of climate change, more is needed to save Britain’s seabirds.</p>
<h2>The significance of sandeels</h2>
<p>These small, silver, schooling fish pack a large nutritional punch. They feed on zooplankton and are a vital source of food for <a href="https://doi.org/10.1111/j.0022-1112.2004.00400.x">larger fish</a> such as cod, haddock and whiting, as well as <a href="https://doi.org/10.3354/meps08232">top predators such as seals</a>. </p>
<p>Sandeels are also a favourite food for seabirds such as surface-feeding gulls and terns, and deep-diving auk species including puffins, razorbills and guillemots.</p>
<p>As well as falling foul of marine predators, sandeels are caught by humans, largely to be used as <a href="https://doi.org/10.1093/icesjms/fst087">feed for farmed fish</a>, such as salmon, or livestock. The sandeel fishing grounds around the UK are jointly managed by the UK and the European Union. </p>
<p>But the UK government has not allowed British vessels to fish for sandeels <a href="https://www.gov.scot/publications/sandeel-prohibition-fishing-scotland-order-2024-final-business-regulatory-impact-assessment/">since 2021</a>. Instead, commercial fishing for sandeels has most recently been carried out by European vessels, <a href="https://www.gov.scot/publications/sandeel-prohibition-fishing-scotland-order-2024-final-business-regulatory-impact-assessment/">particularly those from Denmark</a> that regularly fish in UK waters during the summer. </p>
<p>Data from the Marine Management Organisation suggests that an average of <a href="https://www.gov.scot/publications/sandeel-prohibition-fishing-scotland-order-2024-final-business-regulatory-impact-assessment/">257,000 tonnes of sandeels</a> were caught annually by EU vessels between 2015 and 2019.</p>
<p>One of the major sandeel fishing areas in the North Sea, a 21,000km2 area off the east coast of Scotland and northeast England called <a href="https://marine.gov.scot/sma/assessment/case-study-sandeels-scottish-waters#:%7E:text=The%20largest%20of%20the%20sandeel,one%20with%20an%20active%20fishery.">sandeel area 4</a>, has been closed to both UK and EU vessels since 2000 – although a small scientific fishery continued to conduct stock assessments <a href="https://data.marine.gov.scot/dataset/monitoring-consequences-northwestern-north-sea-sandeel-fishery-closure">during this time</a>. </p>
<p>Following the area’s closure, sandeel numbers grew and that corresponded with an initial increase in the number of fledged chicks in <a href="https://doi.org/10.1139/f07-164">black-legged kittiwakes</a>, an iconic gull species that has declined in recent decades.</p>
<p>Elsewhere in the world, closures of other “forage fish” fisheries (those that catch species that are prey for larger predators) have revealed positive impacts. African penguins rear more chicks in years when anchovy and sardine fishery areas off the coastline of <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2017.2443">South Africa are closed</a>.</p>
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<img alt="Small thin silver fish dead laying on brown fishing net" src="https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=481&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=481&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=481&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=605&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=605&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574503/original/file-20240208-18-xt7od3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=605&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Sandeels are caught for use as food within the fish farming industry.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/small-sandeel-on-fish-net-1312001660">Coulanges/Shutterstock</a></span>
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<p>As well as removing sandeels from the sea, industrial fishing can <a href="https://doi.org/10.1093/icesjms/fss155">disturb them</a> and drive them to different locations or to deeper depths, away from the hungry beaks of kittiwakes that catch prey for themselves and their chicks at the sea’s surface. </p>
<p>Relationships between the closure of sandeel area 4 and the breeding success of other sandeel-reliant seabirds around northern England and Scotland have not been obvious. This is potentially due to differences in foraging ranges and diving abilities between <a href="https://doi.org/10.1890/07-0797.1">different seabirds</a>. </p>
<p>For kittiwakes, breeding success initially rose after the closures until 2018, but did not bounce right back to the levels observed before <a href="https://doi.org/10.1016/j.biocon.2023.109990">fishing here began</a>, despite 20 years of potential recovery time. This suggests that other factors influence breeding success in kittiwake colonies. </p>
<h2>Climate drivers</h2>
<p>Studies of the impacts that <a href="https://doi.org/10.1016/j.fishres.2017.05.018">forage fishery closures</a> have on seabirds consistently flag the importance of environmental influences. Although fisheries could <a href="https://doi.org/10.1890/07-0797.1">exacerbate declines</a> in <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2017.2443">some seabird species</a>, changing environmental conditions have larger impacts. </p>
<p>Sandeels bury themselves in the sand during the winter and come out during the day to feed in the summer, but warmer temperatures can cause them to emerge from the sand <a href="https://doi.org/10.1002/ece3.8310">earlier in the year</a>. This change might have detrimental <a href="https://doi.org/10.3354/meps09520">knock-on effects</a> on the seabirds that feed sandeels to their chicks during their summer breeding seasons.</p>
<p>Climate change, which has already given rise to a <a href="https://www.mccip.org.uk/sites/default/files/2023-03/The%20Impacts%20of%20Climate%20Change%20on%20Sea%20Temperature%20around%20the%20UK%20and%20Ireland.pdf">warmer North Sea</a>, is a main driver of <a href="https://doi.org/10.1111/fog.12246">sandeel declines</a>. This has important ramifications for birds and other animals higher up the food chain. </p>
<p>The <a href="https://jncc.gov.uk/our-work/seabirds-count/">fourth national seabird census</a> (2015–2021) revealed that more than half the seabird species breeding around Britain and Ireland’s coastlines have declined over the past 20 years. Many of these declines have been linked to the influence of climate change on the availability of their prey. </p>
<p>The government’s environmental watchdog, the Office for Environmental Protection, recently warned that the government’s progress on its promise to stem declines in British nature by 2030 <a href="https://www.theoep.org.uk/report/government-remains-largely-track-meet-its-environmental-ambitions-finds-oep-annual-progress">has been scant</a>. The halting of sandeel fishing around Scotland and northern England is not enough to conserve the seabirds that breed around our coastlines. A more ambitious plan is called for.</p>
<p>Achieving the sandeel fisheries closure involved an immense lobbying effort that has been backed up by <a href="https://www.rspb.org.uk/whats-happening/news/sandeel-campaign-success-in-england">scientific evidence</a>. This success has demonstrated the importance that the British public places on protecting nature. Now, the government ought to not only combine fisheries closures with effective monitoring, but to diverge from burning fossil fuels that continue to heat our planet and choke conservation efforts. </p>
<p>Ultimately, to ensure that healthy sandeel populations will support seabirds in the future, we need to maintain cool seas that will allow their stocks to bounce back to pre-fishing levels.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>Ruth Dunn has previously received funding from the Natural Environment Research Council (NERC).</span></em></p>Many seabird colonies around UK coastlines struggle to breed because the sandeels they feed on have been overfished. The upcoming closure of sandeel fisheries will be good news for marine wildlife.Ruth Dunn, Senior Research Associate in Marine Ecology, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2218062024-02-02T17:35:14Z2024-02-02T17:35:14ZHow trophy fishing can have a sustainable future<figure><img src="https://images.theconversation.com/files/572280/original/file-20240130-29-g3zie3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Blue sharks are popular targets of a catch-and-release fishery along the southern coast of England</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/magnificent-blue-shark-elegant-proud-look-2318078271">Vladimir Turkenich/Shutterstock</a></span></figcaption></figure><p>It was 1984, and a hot tropical sun beat down on the inky blue depths of the Huon Gulf, a large inlet of the Solomon Sea just off the coast of Papua New Guinea. Suddenly, the peace was broken by the scream of a fishing reel as a four-metre-long blue marlin (<em>Makaira mazaraburst</em>) burst from the water. </p>
<p>For the next hour the giant fish surged, leapt and tail walked, as my best friend and fishing companion mostly just held on. Then, suddenly, it was gone. </p>
<p>The trace had frayed. No fishermen likes to lose a fish, but for me, there was also a sense of relief that it had got away. That fish was the most magnificent creature I’d ever seen, and that moment helped inspire my lifelong career in marine biology.</p>
<p>Recreational fishing for the largest species and individual fish in the sea like this is often called trophy fishing. Anglers seek to set new size records, either overall or using particular line strengths. These can be incredible specimens – the <a href="https://www.marlinmag.com/biggest-marlin-ever-caught/">largest marlin ever caught</a> weighed over 700kg, similar to a small car. </p>
<h2>What’s the catch?</h2>
<p><a href="https://onlinelibrary.wiley.com/doi/10.1002/aqc.4051">In a new paper</a>, we analysed 80 years of trophy fishing world records, using data recorded by the International Game Fishing Association (IGFA) to reveal some intriguing trends. Notably, in the 1950s, the average record-holding fish weighed a hefty 168kg, but this figure fell drastically to just 8kg in the 2010s. </p>
<p>The fish are not shrinking, instead anglers are now targeting a broader range of smaller species. However, this might signal a concerning decline in the population of larger fish species.</p>
<p>There has also been a noticeable expansion of trophy fishing worldwide. While the US dominated the scene historically, recent decades have seen an uptick in records from regions like Japan and New Zealand. </p>
<p>This global spread offers potential social and economic benefits to these new areas, but also raises concerns about increased fishing pressure on local fish populations that were previously less targeted.</p>
<p>Perhaps our most significant observation was the sharp decline in new records for fish species listed as threatened with extinction by the International Union for Conservation of Nature. Comparing the last decade (2010–2018) to the 2000s, there has been a roughly 66% decrease in records for these at-risk species. </p>
<p>This trend could indicate a growing awareness towards conservation issues in trophy fishing or could reflect the worrying reality of diminished populations of these species. The exact implications of this trend are yet to be fully understood.</p>
<p>Trophy fishing is controversial. Some people will never be fans. The largest fish in the ocean are often <a href="https://academic.oup.com/icesjms/article/71/8/2171/748104">the most productive breeders</a>, so catching and killing them, especially threatened species, doesn’t make sense. However, while world record fish accredited by the IGFA gain the spotlight, they account for a very small number of fish in total. </p>
<p>Much more concerning are the fishing tournaments that offer <a href="https://www.bisbees.com/News/Article/166">highly lucrative prizes</a> for landing the largest and most fish and <a href="https://sharkallies.org/shark-fishing-tournaments">sharks</a> in a given period of time. </p>
<h2>Tackling sustainability</h2>
<p>Trophy fishing, and sport fishing in general, is changing to become more sustainable, and even a force for good. In 2011, the IGFA introduced the <a href="https://igfa.org/announcement/igfa-launches-all-tackle-length-record-release-category/">“all-tackle length” category</a>. This approach records the length of the fish rather than weight, enabling it to be released without needing to kill it. </p>
<p>The Shark Angling Club of Great Britain has been releasing all sharks for decades and the <a href="https://anglingtrust.net/2023/11/22/update-from-british-record-fish-committee/">British Record Fish Committee</a> recently decided to only allow length-based records for large sharks, with fish having to be measured while still in the water. Although releasing fish does not guarantee survival, that can be maximised by using <a href="https://academic.oup.com/conphys/article/11/1/coad100/7503354">the right gear and careful handling</a>. Such approaches should become mandatory for all trophy anglers.</p>
<p>Anglers dedicate extensive time to their passion, developing a wealth of knowledge about the fish they catch. Harnessing this expertise is crucial for better estimating the extent of trophy fishing and increasing knowledge of fish stocks in general. </p>
<p>In the UK, anglers and scientists are working together through initiatives such as <a href="https://anglingtrust.net/sea/sea-angling-science/shark-hub-uk/">Shark Hub UK</a> and <a href="https://anglingtrust.net/sea/sea-angling-science/pollack-project/">Project Pollack</a> to gather catch data, collect samples and tag fish. </p>
<p>This approach not only aids conservation efforts but also aligns with the anglers’ interest in maintaining healthy fish populations for the future. After all, the recreational fisheries are not only a source of livelihood but also contribute to the <a href="https://www.mdpi.com/2673-3986/4/3/30">mental and physical wellbeing</a> of those who engage with them.</p>
<p>Nearly 40 years after that experience in Papua New Guinea, I marvelled at huge schools of giant fish off the coast of southern England last summer. These Atlantic bluefin tuna (<em>Thunnus thynnus</em>) have had <a href="https://academic.oup.com/icesjms/article/78/5/1672/6231587?login=false">a remarkable recovery</a> around the coast, most likely due to a combination of improved management and changing environmental conditions. </p>
<p>From this year, the UK government has authorised a <a href="https://www.gov.uk/government/news/recreational-fishing-for-atlantic-bluefin-tuna-set-to-start-in-english-waters-next-year#:%7E:text=Each%20UK%20fisheries%20administration%20will,commercial%20fishery%20for%20bluefin%20tuna.">catch and release only recreational fishery</a> for these fish. With continued careful management this should bring exciting angling, social and economic benefits for years to come.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p class="fine-print"><em><span>Bryce Stewart receives funding from Defra and UK Research and Innovation. He is a member of the Marine Conservation Society and the Yorkshire Wildlife Trust and sits on the Marine Stewardship Council Stakeholder Advisory Council.</span></em></p><p class="fine-print"><em><span>James Boon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Trophy fishing is a big threat to some of the most threatened species of fish, but there are ways to adapt the sport with marine conservation in mind.Bryce Stewart, Senior research fellow, Marine Biological AssociationJames Boon, PhD candidate in Marine Ecology, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2225112024-02-02T11:04:44Z2024-02-02T11:04:44ZGovernments spend US$22 billion a year helping the fishing industry empty our oceans. This injustice must end<figure><img src="https://images.theconversation.com/files/572830/original/file-20240201-27-sdoziy.jpg?ixlib=rb-1.1.0&rect=2%2C0%2C1370%2C770&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.pexels.com/photo/drone-view-of-fishing-trawler-on-sea-5829126/">Pok Rie/Pexel</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Overfishing has dire consequences for ocean health and for the millions of people who depend on fish for food and wellbeing. Globally, catch has been steadily <a href="https://www.nature.com/articles/ncomms10244">declining</a> since the 1990s. It’s a trend that’s likely to continue if we fail to act now.</p>
<p>Nearly all governments, including Australia’s, subsidise their fishing industries. Financial support comes in many forms, from taxpayer-funded fuel to reduced boat-building costs. These subsidies are harmful because they encourage overfishing. Some of the most environmentally damaging and least efficient fishing activities, such as <a href="https://www.sciencedirect.com/science/article/abs/pii/S0308597X09001663">bottom trawling</a> and <a href="https://www.science.org/doi/full/10.1126/sciadv.aat2504">distant water fishing</a>, would become unprofitable and cease without government <a href="https://archives.nereusprogram.org/ask-an-expert-why-is-the-global-fishing-industry-given-35-billion-in-subsidies-each-year/">subsidies</a>. </p>
<p>Scientists worldwide are rallying for stringent regulations to eliminate harmful fisheries subsidies, which totalled a whopping <a href="https://www.sciencedirect.com/science/article/pii/S0308597X19303677">US$22 billion</a> in 2018. Safeguarding the ocean will strengthen food security and allow more equitable distribution of marine resources.</p>
<p>Trade ministers from around the world are set to convene later this month in Abu Dhabi at a key meeting of the World Trade Organization (WTO). In an <a href="https://www.nature.com/articles/s44183-024-00042-0">open letter</a> published today, we are among 36 marine experts calling on the WTO to adopt ambitious regulations promoting fisheries sustainability and equity, and to eliminate harmful fisheries subsidies.</p>
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<strong>
Read more:
<a href="https://theconversation.com/putting-an-end-to-billions-in-fishing-subsidies-could-improve-fish-stocks-and-ocean-health-163470">Putting an end to billions in fishing subsidies could improve fish stocks and ocean health</a>
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<h2>A long-awaited agreement</h2>
<p>International pressure from scientists helped to broker an earlier agreement on fishing subsidies, which is yet to be ratified. </p>
<p>In October 2021, 300 experts published an <a href="https://www.science.org/doi/10.1126/science.abm1680">article in Nature</a> calling for an end to harmful subsidies in the fishing sector. </p>
<p>After decades of fruitless negotiations, the WTO finally reached an <a href="https://www.wto.org/english/tratop_e/rulesneg_e/fish_e/fish_factsheet_e.pdf">agreement on fisheries subsidies</a> in June 2022. </p>
<p>Once ratified by two-thirds of WTO members, this agreement will partially address the United Nations <a href="https://indicators.report/targets/14-6/">Sustainable Development Goal Target 14.6</a> to eliminate harmful subsidies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man in a suit brings down the gavel after agreement was reached on fisheries subsidies at the WTO meeting in 2022." src="https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572831/original/file-20240201-17-tiyvdp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The gavel goes down after members reached an agreement on fisheries subsidies, Geneva, 17 June 2022.</span>
<span class="attribution"><a class="source" href="https://www.wto.org/english/thewto_e/minist_e/mc12_e/photos_e.htm">WTO/Jay Louvion</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>Unfortunately, while this agreement is historic, it is narrow. It only prohibits member governments from financing illegal fishing activities and the exploitation of already overfished stocks. But it’s obvious illegal fishing should be banned and the focus on overfished stocks is too little, too late. </p>
<p>Experts argue the agreement fails to specifically address harmful subsidies across global fisheries and as such only affects a <a href="https://oceana.org/blog/the-wto-agreement-saves-face-but-does-it-save-fish/">trivial component</a> of subsidy-driven exploitation. The subsidies that reduce operating costs and increase fishing capacity, allowing vessels to travel further and remain at sea longer, remain in place. </p>
<h2>Fisheries subsidies affect more than just fish</h2>
<p>Scientists have been <a href="https://www.nature.com/articles/s43016-021-00451-1">sounding the alarm</a> for decades. Many published studies document the <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0020239">destabilising effects</a> of fisheries subsidies on ecosystems. In addition to impacting biodiversity and ecosystems, subsidies also increase the <a href="https://www.sciencedirect.com/science/article/abs/pii/S0921800921001154">CO₂ emissions</a> that contribute to climate change.</p>
<p>More recently, studies have also applied a social perspective to this issue. Seafood lifts millions of people out of hunger, malnutrition and poverty. Yet more people will lose a secure <a href="https://www.nature.com/articles/534317a">source of food and nutrients</a> if fish stocks continue to decline due to industrial overfishing. </p>
<p>Research shedding light on the concept of “<a href="https://www.sciencedirect.com/science/article/pii/S0308597X20302529">equity</a>” shows subsidies don’t just harm the ocean, they also affect human <a href="https://www.worldwildlife.org/stories/5-ways-harmful-fisheries-subsidies-impact-coastal-communities">communities</a>. These communities are largely in developing countries which are rarely the source of harmful fisheries subsidies. Rather, their waters are exploited by <a href="https://oceana.org/wp-content/uploads/sites/18/OceanaDWF_FinalReport.pdf">foreign vessels</a> supported by wealthy governments’ fisheries subsidies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person wearing gloves, bending down to handle drying squid on a fish net" src="https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572832/original/file-20240201-25-bknp4o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Fisheries contribute to livelihoods and food security of millions of people.</span>
<span class="attribution"><a class="source" href="https://www.pexels.com/photo/person-drying-squid-on-fishnet-13243896/">Jimmy Liao/Pexel</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>Fisheries subsidies foster unfair competition not only among countries but also between industrial and community led fishing fleets. In the <a href="https://www.nature.com/articles/s44183-023-00031-9">Indian Ocean</a>, the level of subsidies provided to industrial fisheries corresponds to the amount of seafood exported to international markets, largely supplying rich and food-secure countries. This shows governments are deliberately empowering their industrial fleets to fish for seafood largely exported and consumed elsewhere, instead of sustaining fisheries providing food for locals. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fisheries-subsidies-fuel-ocean-depletion-and-hurt-coastal-communities-142260">Fisheries subsidies fuel ocean depletion and hurt coastal communities</a>
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<hr>
<h2>The good, the bad and the ugly</h2>
<p>While most nations contribute to harmful subsidies, <a href="https://oceana.org/wp-content/uploads/sites/18/994812/Oceana_Summary6-22.pdf">ten nations</a> are responsible for 70% of this unsustainable financing. Chief among them are China, Japan and the European Union, reflecting the significant size of their distant water fishing fleets that typically access the resources of less-developed nations.</p>
<p>In contrast, <a href="https://www.sciencedirect.com/science/article/pii/S0308597X19303677?via%3Dihub">Australia</a> contributes only 0.1% of global harmful subsidies. Only 6% of Australia’s annual US$400 million in fisheries subsidies is considered harmful. While Australia should give attention to its ongoing annual taxpayer contribution of US$25 million to the fishing sector, it is well placed to demonstrate global leadership on how fishing can deliver sustainable and equitable outcomes without harmful subsidies.</p>
<h2>An essential opportunity</h2>
<p>A <a href="https://www.wto.org/english/thewto_e/minist_e/mc13_e/mc13_e.htm">second wave</a> of negotiations on fisheries subsidies is expected during the WTO Ministerial Conference this February in Abu Dhabi. This conference represents an invaluable opportunity to better protect the ocean. </p>
<p>In anticipation of this meeting, <a href="https://www.nature.com/articles/s44183-024-00042-0">we are urging nations</a> to adopt more ambitious regulations that eliminate harmful subsidies, prioritising fisheries sustainability and ocean equity. </p>
<p>Harmful fisheries subsidies are not only unsustainable but profoundly unfair. Based on the extensive body of evidence, the WTO should agree to eliminate harmful subsidies once and for all.</p><img src="https://counter.theconversation.com/content/222511/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Vania Andreoli received funding for her PhD research from the Australian Government Research Training Program Scholarship and The Jock Clough Marine Foundation through the Oceans Institute Robson and Robertson Award. </span></em></p><p class="fine-print"><em><span>Dirk Zeller supervises Vania Andreoli’s PhD, so his lab has indirectly received funding for this doctoral research from the Australian Government and the Jock Clough Marine Foundation.</span></em></p><p class="fine-print"><em><span>Jessica Meeuwig supervises Vania Andreoli's PhD so her lab has indirectly received funding for this doctoral research from the Australian Government and the Jock Clough Marine Foundation. </span></em></p>Governments all over the world are propping up overfishing. Now scientists have penned an open letter calling on trade ministers to implement stricter regulations against harmful fisheries subsidies.Vania Andreoli, PhD Candidate, The University of Western AustraliaDirk Zeller, Professor & Director, Sea Around Us - Indian Ocean, The University of Western AustraliaJessica Meeuwig, Wen Family Chair in Conservation, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2193672024-01-03T16:00:11Z2024-01-03T16:00:11ZWe used AI and satellite imagery to map ocean activities that take place out of sight, including fishing, shipping and energy development<figure><img src="https://images.theconversation.com/files/566911/original/file-20231220-19-b20mqb.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4839%2C3265&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Many commercial fishing boats do not report their positions at sea or are not required to do so.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/aerial-view-of-small-fishing-boat-in-open-ocean-royalty-free-image/1285320085">Alex Walker via Getty Images</a></span></figcaption></figure><p>Humans are racing to harness the ocean’s vast potential to power global economic growth. Worldwide, ocean-based industries such as fishing, shipping and energy production generate at least <a href="https://doi.org/10.1787/9789264251724-en">US$1.5 trillion</a> in economic activity each year and support <a href="https://doi.org/10.1787/9789264251724-en">31 million jobs</a>. This value has been <a href="https://doi.org/10.1016/j.oneear.2019.12.016">increasing exponentially</a> over the past 50 years and is expected to double by 2030. </p>
<p>Transparency in monitoring this “blue acceleration” is crucial to prevent <a href="http://dx.doi.org/10.5281/zenodo.3553458">environmental degradation</a>, <a href="https://doi.org/10.4060/cc0461en">overexploitation</a> of fisheries and marine resources, and <a href="https://www.newyorker.com/magazine/2023/10/16/the-crimes-behind-the-seafood-you-eat">lawless behavior</a> such as illegal fishing and human trafficking. Open information also will make countries better able to manage vital ocean resources effectively. But the sheer size of the ocean has made tracking industrial activities at a broad scale impractical – until now.</p>
<p>A newly published study in the journal Nature combines satellite images, vessel GPS data and artificial intelligence to <a href="https://dx.doi.org/10.1038/s41586-023-06825-8">reveal human industrial activities across the ocean</a> over a five-year period. Researchers at <a href="https://globalfishingwatch.org/">Global Fishing Watch</a>, a nonprofit organization dedicated to advancing ocean governance through increased transparency of human activity at sea, led this study, in collaboration with <a href="https://scholar.google.com/citations?user=ArWZ7X0AAAAJ&hl=en">me</a> and our colleagues at Duke University, University of California, Santa Barbara and <a href="https://skytruth.org/">SkyTruth</a>.</p>
<p>We found that a remarkable amount of activity occurs outside of public monitoring systems. Our new map and data provide the most comprehensive public picture available of industrial uses of the ocean.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A world map shows large areas where industrial fishing activity is not publicly tracked or recorded." src="https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=309&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=309&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=309&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=388&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=388&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566373/original/file-20231218-27-k4cjbr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=388&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Data analysis reveals that about 75% of the world’s industrial fishing vessels are not publicly tracked, with much of that fishing taking place around Africa and South Asia.</span>
<span class="attribution"><span class="source">Global Fishing Watch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Operating in the dark</h2>
<p>Our research builds on existing technology to provide a much more complete picture than has been available until now. </p>
<p>For example, many vessels carry a device called an automatic identification system, or AIS, that automatically broadcasts the vessel’s identity, position, course and speed. These devices <a href="https://shipping.nato.int/nsc/operations/news/2021/ais-automatic-identification-system-overview">communicate with other AIS devices nearby</a> to improve situational awareness and reduce the chances of vessel collisions at sea. They also transmit to shore-based transponders and satellites, which can be used to <a href="https://globalfishingwatch.org/our-map/">monitor vessel traffic and fishing activity</a>.</p>
<p>However, AIS systems have blind spots. Not all vessels are required to use them, certain regions have poor AIS reception, and vessels engaged in illegal activities may <a href="https://theconversation.com/when-fishing-boats-go-dark-at-sea-theyre-often-committing-crimes-we-mapped-where-it-happens-196694">disable AIS devices</a> or <a href="https://youtu.be/Azm4yKKIlqE?si=vvng8to_Hsa13E1p">tamper with location broadcasts</a>. To avoid these problems, some governments require fishing vessels to use proprietary vessel monitoring systems, but the associated vessel location data is usually confidential.</p>
<p>Some offshore structures, such as oil platforms and wind turbines, <a href="https://www.amsa.gov.au/safety-navigation/navigation-systems/automatic-identification-systems-offshore-structures">also use AIS</a> to guide service vessels, monitor nearby vessel traffic and improve navigational safety. However, location data for offshore structures are often incomplete, outdated or kept confidential for bureaucratic or commercial reasons.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Fishermen wade into the ocean, pulling large nets." src="https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566375/original/file-20231218-23-bd69hf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fishermen haul their nets by hand from the beach in Muanda, Democratic Republic of Congo. Unregulated fishing by foreign trawlers and other factors have depleted fishing stocks and impoverished local fishermen.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/fishermen-haul-their-nets-by-hand-from-the-beach-in-muanda-news-photo/1237283044">Alexis Huguet/AFP via Getty Images</a></span>
</figcaption>
</figure>
<h2>Shining a light on activity at sea</h2>
<p>We filled these gaps by using artificial intelligence models to identify fishing vessels, nonfishing vessels and fixed infrastructure in 2 million gigabytes of satellite-based <a href="https://sentinels.copernicus.eu/web/sentinel/missions/sentinel-1">radar images</a> and <a href="https://sentinel.esa.int/web/sentinel/missions/sentinel-2">optical images</a> taken across the ocean between 2017 and 2021. We also matched these results to 53 billion AIS vessel position reports to determine which vessels were publicly trackable at the time of the image.</p>
<p>Remarkably, we found that about 75% of the fishing vessels we detected were missing from public AIS monitoring systems, with much of that activity taking place around Africa and South Asia. These previously invisible vessels radically changed our knowledge about the scale, scope and location of fishing activity.</p>
<p>For example, public AIS data wrongly suggests that Asia and Europe have comparable amounts of fishing within their borders. Our mapping reveals that Asia dominates: For every 10 fishing vessels we found on the water, seven were in Asia while only one was in Europe. Similarly, AIS data shows about 10 times more fishing on the European side of the Mediterranean compared with the African side – but our map shows that fishing activity is roughly equal across the two areas.</p>
<p>For other vessels, which are mostly transport- and energy-related, about 25% were missing from public AIS monitoring systems. Many missing vessels were in locations with poor AIS reception, so it is possible that they broadcast their locations but satellites did not pick up the transmission.</p>
<p>We also identified about 28,000 offshore structures – mostly oil platforms and wind turbines, but also piers, bridges, power lines, aquaculture farms and other human-made structures. Offshore oil infrastructure grew modestly over the five-year period, while the number of wind turbines more than doubled globally, with development mostly confined to northern Europe and China. We estimate that the number of wind turbines in the ocean likely surpassed the number of oil structures by the end of 2020.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="World map with locations of wind turbines, oil and gas platforms and other structures highlighted along coastlines." src="https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=309&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=309&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=309&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=388&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=388&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566913/original/file-20231220-23-fa89lc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=388&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers combined machine learning and satellite imagery to create the first global map of offshore infrastructure, spotlighting previously unmapped industrial use of the ocean.</span>
<span class="attribution"><span class="source">Global Fishing Watch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Supporting real-world efforts</h2>
<p>This data is freely available through the Global Fishing Watch <a href="https://globalfishingwatch.org/datasets-and-code/">data portal</a> and will be maintained, updated and expanded over time there. We anticipate several areas where the information will be most useful for on-the-ground monitoring:</p>
<p>– <strong>Fishing in data-poor regions</strong>: Shipboard monitoring systems are too expensive to deploy widely in many places. Fishery managers in developing countries can use our data to monitor pressure on local stocks. </p>
<p>– <strong>Illegal, unreported and unregulated fishing</strong>: Industrial fishing vessels sometimes operate in places where they should not be, such as <a href="https://hakaimagazine.com/news/the-african-coastline-is-a-battleground-for-foreign-fleets-and-artisanal-fishers/">small-scale and traditional fishing grounds</a> and <a href="https://www.businessinsider.com/fishing-illegal-oceana-going-dark-marine-protected-areas-2018-4">marine protected areas</a>. Our data can help enforcement agencies identify illegal activities and target patrol efforts.</p>
<p>– <strong>Sanction-busting trade</strong>: Our data can shed light on maritime activities that may breach international economic sanctions. For example, <a href="https://www.un.org/securitycouncil/sanctions/1718/resolutions">United Nations sanctions</a> prohibit North Korea from exporting seafood products or selling its fishing rights to other countries. Previous work <a href="https://doi.org/10.1126/sciadv.abb1197">found more than 900 undisclosed fishing vessels</a> of Chinese origin in the eastern waters of North Korea, in violation of U.N. sanctions. </p>
<p>We found that the western waters of North Korea had far more undisclosed fishing, likely also of foreign origin. This previously unmapped activity peaked each year in May, when China bans fishing in its own waters, and abruptly fell in 2020 when North Korea closed its borders because of the COVID-19 pandemic.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ZRLW-3Niseg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Better monitoring may help nations coordinate offshore activities in busy regions like the North Sea.</span></figcaption>
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<p>– <strong>Climate change mitigation and adaptation</strong>: Our data can help quantify the scale of greenhouse gas emissions from vessel traffic and offshore energy development. This information is important for enforcing climate change mitigation programs, such as the European Union’s <a href="https://climate.ec.europa.eu/eu-action/transport/reducing-emissions-shipping-sector_en">emissions trading scheme</a>. </p>
<p>– <strong>Offshore energy impacts</strong>: Our map shows not only where offshore energy development is happening but also how vessel traffic interacts with wind turbines and oil and gas platforms. This information can shed light on the environmental footprint of building, maintaining and using these structures. It can also help to <a href="https://skytruth.org/cerulean/">pinpoint sources of oil spills</a> and other marine pollution. </p>
<p>Healthy oceans <a href="https://oceanservice.noaa.gov/facts/why-care-about-ocean.html">underpin human well-being</a> in a myriad of ways. We expect that this research will support evidence-based decision-making and help to make ocean management more fair, effective and sustainable.</p>
<p><em>Fernando Paolo, senior machine learning engineer at Global Fishing Watch; David Kroodsma, director of research and innovation at Global Fishing Watch; and Patrick Halpin, Professor of Marine Geospatial Ecology at Duke University, contributed to this article.</em></p><img src="https://counter.theconversation.com/content/219367/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The study described in this article was funded by Oceankind, Bloomberg Philanthropies and National Geographic Pristine Seas. The European Space Agency made radar and optical imagery freely available, and Google provided computing resources and technical support. Jennifer Raynor has worked at National Oceanic and Atmospheric Administration Fisheries, and currently serves on the Board of Trustees for Global Fishing Watch.</span></em></p>A new study reveals that 75% of the world’s industrial fishing vessels are hidden from public view.Jennifer Raynor, Assistant Professor of Natural Resource Economics, University of Wisconsin-MadisonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2174282023-12-14T22:14:08Z2023-12-14T22:14:08ZClimate change is further reducing fish stocks with worrisome implications for global food supplies<figure><img src="https://images.theconversation.com/files/565799/original/file-20231214-17-9k9tr0.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4000%2C3000&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Seafood is a ubiquitous human food-source, the future stability of which is uncertain.</span> <span class="attribution"><span class="source">(Pexels)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/climate-change-is-further-reducing-fish-stocks-with-worrisome-implications-for-global-food-supplies" width="100%" height="400"></iframe>
<p>The health benefits of eating seafood are appreciated in many <a href="https://www.fao.org/3/cc0461en/online/sofia/2022/consumption-of-aquatic-foods.html">cultures</a> which rely upon it to provide critical nutrients vital to our <a href="https://doi.org/10.1016/bs.afnr.2021.04.001">physical and mental development and health</a>. Eating fish and shellfish provides significant benefits to <a href="https://doi.org/10.1038/nrn3820">neurological development and functioning</a> and provides protection against the risks of <a href="https://doi.org/10.1038/s43016-019-0013-1">coronary heart disease and Type 2 diabetes</a>. </p>
<p>Over three billion people get at least 20 per cent of their daily animal protein from fish. In countries from Bangladesh to Cambodia, Gambia, Ghana, Indonesia, Sierra Leone and Sri Lanka, <a href="https://www.fao.org/3/ca9229en/ca9229en.pdf">fish consumption accounts for 50 per cent or more</a> of daily intake.</p>
<p>However, expansive growth of human populations globally puts immense pressure on the health of wild fish stocks. Fish catches <a href="https://doi.org/10.1038/ncomms10244">peaked in 1996</a>, and <a href="https://www.fao.org/state-of-fisheries-aquaculture">one-third are considered overexploited</a>. With less fish available to still more people, the future of fish as an accessible source of nutritious food is at risk, particularly among low-income countries.</p>
<h2>Seafood nutrient losses</h2>
<p>Threats to seafood access aren’t just due to overharvesting. There is a growing body of research showing that higher water temperatures due to climate change can impact the <a href="https://doi.org/10.1038/nature12156">presence and abundance of the catch</a>, through shifts in species distribution and changes in the species caught. This impacts the amount that can be harvested, as well as the nutritional value of that harvest.</p>
<p>A <a href="https://doi.org/10.1038/s41558-023-01822-1">new study</a> (which Aaron MacNeil contributed to) quantified nutrient availability from seafood through time considering the twin impacts of overfishing and climate change. </p>
<p>Focusing on four key nutrients important to human health — calcium, iron, omega-3 fatty acids and protein — the authors argue that nutrient availability in seafood has been declining since 1990 and will further decline by around 30 per cent by 2100 in predominately tropical, low-income countries with 4 C of warming.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-climate-change-induced-stress-is-altering-fish-hormones-with-huge-repercussions-for-reproduction-213140">How climate change-induced stress is altering fish hormones — with huge repercussions for reproduction</a>
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<p>These predicted losses are significant. While global famines are now relatively rare, some <a href="https://doi.org/10.1016/j.gfs.2020.100480">50 million people suffer from “hidden hunger”</a> — nutrient-deficient diets that are masked by being otherwise calorie-sufficient. </p>
<p>For animal-derived nutrients such as B12 and omega-3 fatty acids, <a href="https://doi.org/10.1038/534317a">nearly 20 per cent of the global population are at risk of becoming nutrient-deficient</a> in coming decades due to reliance on wild-caught fish.</p>
<p>Climate change is also affecting natural cycles of nutrients in the ocean. For example, it has been predicted that increasing water temperatures will cause a <a href="https://doi.org/10.1007/s13280-019-01234-6">decline in natural omega-3 availability from seafood by more than 50 per cent by 2100</a>. At the bottom of the food chain, microalgae that naturally produce omega-3s <a href="https://doi.org/10.1111/gcb.13295">are less productive at warmer temperatures</a> and this cascades through marine and freshwater food chains resulting in fish having less omega-3s available to eat and store in their bodies. </p>
<figure class="align-center ">
<img alt="Men standing on three small boats cast nets into the ocean." src="https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565818/original/file-20231214-15-s4v8j4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The global problems of climate change and overfishing have led to decreasing availability of seafood for millions around the world.</span>
<span class="attribution"><span class="source">(Pexels)</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>These kinds of climate-caused losses are expected to disproportionately affect vulnerable populations, especially in inland Africa.</p>
<h2>Challenges and strategies for nutritious seafood</h2>
<p>Aquaculture can help supply some of these missing nutrients, but it is an industry also vulnerable to the effects of climate change. A <a href="https://doi.org/10.3389/fsufs.2021.609097">recent study</a> predicted that 90 per cent of aquaculture will be impacted by climate change, where warm waters increase <a href="https://www.jstor.org/stable/26920865">disease outbreaks, harmful algal blooms and impact the availability of feed supplies</a>.</p>
<p><a href="https://www.un.org/en/global-issues/food">Global disparities already exist in food security</a> that will be exacerbated by climate change in the future. Yet the effects of warming waters on nutrient availability from seafood will compound these inequities among tropical and low-income countries. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-future-of-fishing-and-fish-and-the-health-of-the-ocean-hinges-on-economics-and-the-idea-of-infinity-fish-182749">The future of fishing and fish — and the health of the ocean — hinges on economics and the idea of 'infinity fish'</a>
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<p>These results suggest a major challenge to our future nutritional security that demands strong fisheries and aquaculture management to facilitate equitable distribution of nutritious seafoods. </p>
<p>Improvements are possible. </p>
<p>For example, <a href="https://doi.org/10.1038/s41586-019-1592-6">redirecting nine per cent of Namibia’s fisheries toward its coastal population</a> would alleviate the severe iron deficiencies experienced there. Policies that prioritize nutrient supply would help maintain diets as the climate warms. </p>
<p>The recent United Nations call to action for <a href="https://www.fao.org/documents/card/en?details=cc0459en/">blue transformation</a> emphasizes the need to provide sufficient aquatic food from fisheries and aquaculture for our growing population in a sustainable way. </p>
<p>To do this, strategies are needed to achieve healthy, equitable and resilient food systems that adequately deal with overfishing, strive for equal access to resources and markets and mitigate the environmental impacts of aquatic food production. </p>
<p>Ultimately, these strategies must support the nutritional security of vulnerable nations and consider global health equity and the cultural significance of seafood.</p><img src="https://counter.theconversation.com/content/217428/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stefanie Colombo receives funding from the Natural Sciences and Engineering Research Council and the Ocean Frontier Institute, through an award from the Canada First Research Excellence Fund. She serves as the Science Advisor for the Aquaculture Association of Nova Scotia. </span></em></p><p class="fine-print"><em><span>Aaron MacNeil receives funding from the Shark Conservation Fund, the Natural Sciences and Engineering Research Council, and the Ocean Frontier Institute, through an award from the Canada First Research Excellence Fund.</span></em></p>Climate change and overfishing are depleting global fish stocks with clear implications for the food security future of billions of people.Stefanie Colombo, Canada Research Chair in Aquaculture Nutrition, Dalhousie UniversityAaron MacNeil, Professor, Department of Biology, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2187762023-12-04T13:26:50Z2023-12-04T13:26:50ZHere’s what happened when I taught a fly-fishing course in the waterways of New Orleans<figure><img src="https://images.theconversation.com/files/563041/original/file-20231201-21-oebp2a.jpg?ixlib=rb-1.1.0&rect=35%2C291%2C3929%2C2835&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mae Bennett, a student in the author's class, practices fly-casting on Lake Pontchartrain in New Orleans. </span> <span class="attribution"><span class="source">Kyle Encar/Loyola University New Orleans </span></span></figcaption></figure><figure class="align-right ">
<img alt="Text saying: Uncommon Courses, from The Conversation" src="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/topics/uncommon-courses-130908">Uncommon Courses</a> is an occasional series from The Conversation U.S. highlighting unconventional approaches to teaching.</em> </p>
<h2>Title of course:</h2>
<p>“The Art of Fly-Fishing” </p>
<h2>What prompted the idea for the course?</h2>
<p>After two years of Zoom classes due to the pandemic, I thought it would be useful to offer a two-week intersession course at Loyola University New Orleans that got students away from their phones and computers. </p>
<p>I had just written <a href="https://www.dukeupress.edu/fly-fishing">a book on fly-fishing</a> and spent years practicing the activity as well as studying its literary representations. To teach the course, I drew on my prior experience as an outdoor guide leading river trips for the company <a href="https://www.oars.com/">OARS</a> in Wyoming.</p>
<p>My students welcomed the opportunity to learn a new skill: <a href="https://www.pinterest.co.uk/pin/489062840776806126/">how to cast a fly rod</a>, which is more active than other types of fishing. This is because the lure or “fly” at the end of the line does not weigh much; the cast is produced by using a weighted line that gains velocity through a carefully timed rhythm. None of the 10 students had previous fly-fishing experience, but took the course on a lark or at the urging of a friend or relative.</p>
<p>What I didn’t anticipate was how social dynamics would affect the course and what my students would get out of the experience by it being situated in our vibrant city. Our class became a roving public forum as we interacted with curious observers and passersby. I was teaching them how to fly-fish in urban bayous and park ponds, not exactly “<a href="https://www.imdb.com/title/tt0105265/">A River Runs Through It</a>.”</p>
<figure class="align-center ">
<img alt="A man stands on rocks and casts a fly-fishing rod in a body of water surrounded by trees." src="https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=315&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=315&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=315&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=396&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=396&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562975/original/file-20231201-15-jdl9dq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=396&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This photo was made into the cover for ‘A River Runs Through It,’ a 1992 film directed by Robert Redford.</span>
<span class="attribution"><a class="source" href="https://www.saatchiart.com/art/Photography-A-River-Runs-Through-It/1071967/4415537/view?fbclid=IwAR02XSDdJeQUgUd50assfw7yMeTU4e2oEErSouiGstLo_Ae6d6bm5W7u8Wk">John Kelly</a></span>
</figcaption>
</figure>
<h2>What does the course explore?</h2>
<p>The course introduced the techniques of fly-fishing and explored what makes it different from other forms of fishing. We learned about different waters and fish species, and how fly-fishing can be used in a variety of conditions. We also discussed the <a href="https://press.uchicago.edu/ucp/books/book/chicago/R/bo26756579.html">literary</a> and <a href="https://www.theparisreview.org/blog/2017/10/10/philosophy-fly-fishing/">philosophical</a> aspects of fly-fishing.</p>
<p>I framed the course as a “field experience,” and it took place entirely off campus and around our city instead. This ended up making the course surprisingly effective. </p>
<p>We first met in a field in City Park, where we had plenty of room to form a wide circle: Casting a fly line requires a lot of space. The students practiced casting toward the center of our circle; this way they could see each other’s forms improve, and I could move around the circle giving tips, advice and encouragement. We used pieces of yarn on the ends of the line to reduce the risk of inadvertent ear-piercings. </p>
<p>Beside this field was a pond. As the students got the basics of casting down, they could head to the shoreline and cast flies – with hooks – into the water. A few students even caught fish: beautiful little bluegills, sunfish and bass.</p>
<p>After a few days in City Park, we fly-fished along the cement-lined Bayou St. John in the heart of Mid-City. Another day we met at Lake Pontchartrain. We spread out to fish, minding the obstacles and obstructions posed by the urban infrastructure, and being careful when joggers or dog walkers passed by.</p>
<p>We gathered occasionally to discuss the theory and practice of fly-fishing. All the while, people would linger and watch with bemusement. It was rare to see fly-fishing in urban New Orleans. </p>
<h2>Why is this course relevant now?</h2>
<p>This course tuned students into our region, ecosystem and environment through a focused activity. </p>
<h2>What’s a critical lesson from the course?</h2>
<p>My students did not just develop an outdoor skill – they interacted with people in the community, blurring the boundaries between their college lives and the social fabric of the city. </p>
<h2>What materials does the course feature?</h2>
<p>On the first day, each student chose a fly-fishing book from a stack I brought, from the <a href="https://www.upress.virginia.edu/title/3154/">literary</a> and <a href="https://www.graywolfpress.org/books/northern-waters">philosophical</a> to the more <a href="https://services.math.duke.edu/education/prep03/FermatsPond/FermatsPond/fish/fish.html">pragmatic</a> and <a href="https://www.patagonia.com/product/simple-fly-fishing-revised-second-edition-techniques-for-tenkara-and-rod-and-reel-book/BK709.html?cgid=books-fishing">instructional</a>. We started each morning by sharing insights and lessons we’d gleaned from our books. In the evenings, we wrote together on a Google Doc, creating a collaborative essay about the course. </p>
<p>I also used a series of <a href="https://farbank.com/pages/learn-fly-fishing-school-videos">online instructional videos on fly-fishing</a> created by outfitter <a href="https://farbank.com">Far Bank</a>, which provided fly rods for my class at a discount that they offer to educators. I purchased the equipment with my professorship funds to spare my students extra expenses. </p>
<h2>What will the course prepare students to do?</h2>
<p>Studies have shown that <a href="https://theconversation.com/what-social-change-movements-can-learn-from-fly-fishing-the-value-of-a-care-focused-message-207284">fly-fishing can foster collective purpose</a> around environmental justice movements. Our course demonstrated how fly-fishing can also translate to public, urban contexts and facilitate positive everyday social interactions. </p>
<p>As my students gained confidence with their fly rods, they also welcomed the questions posed by onlookers who wondered what they were doing. My students would explain what the class was and what fly-fishing entailed. My students were engaging with the public about their college experience.</p>
<p>This past summer I transitioned to another institution, Washington University in St. Louis, where I’m directing a new <a href="https://publicscholarship.wustl.edu">Program in Public Scholarship</a>. I’m not currently teaching, but if I have the chance to propose a course, I’ve been eyeing the lagoons in bustling Forest Park, a short walk from campus – the perfect setting for a redux version of my fly-fishing course.</p><img src="https://counter.theconversation.com/content/218776/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Schaberg does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Students learned not just a practical outdoor skill, but how to explain what they were learning to curious observers.Christopher Schaberg, Director of Public Scholarship, Arts & Sciences at Washington University in St. LouisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2182672023-11-30T13:35:54Z2023-11-30T13:35:54ZDrone fishing in South Africa is a danger to sharks and may be unfair to other fishers – study<p>“Drone fishing” is a relatively recent innovation in the use of unmanned aerial vehicles. Some recreational anglers are using personal drones to fly baited lines into hard-to-reach areas of water, or to look for good fishing areas. </p>
<p>Recreational fishing is a popular sport and hobby in South Africa, which has a 2,850km shoreline. The most recent estimate of the number of marine shore based anglers is about <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1111/fme.12515">400,000</a>. </p>
<p>The group of researchers I’m part of, who study linefish (fish caught using hook and line) became aware over the past 10 years or so of the increased practice of drone fishing. This was in part thanks to recreational fishers approaching us with their concerns. </p>
<p>One of the concerns is that increases in the numbers of enthusiastic anglers and their ability to catch fish might have significant effects on fish stocks and other animals (such as birds) in coastal zones. Another is that drone fishing might intensify conflict between fisher groups competing for the same species. Aside from recreation, linefishing provides the primary source of <a href="https://www.tandfonline.com/doi/abs/10.2989/1814232X.2020.1824738">protein and income</a> for about 2,730 commercial fishers, 2,400 small-scale boat fishers and 30,000 small-scale shore-based fishers in South Africa. </p>
<p>We agreed the practice should be investigated, but faced a challenge: there was very little monitoring going on to provide data. </p>
<p>So we took an unconventional approach to our <a href="https://link.springer.com/article/10.1007/s13280-021-01578-y#Sec11">study</a>. We used publicly available online monitoring to estimate the growing interest, global extent and catch composition of drone fishing. This showed us that there had been a big (357%) spike in interest in drone fishing in 2016. There were also worrying indications of a threat to species of conservation concern in South Africa. </p>
<p>We then consulted commercial drone operators, legal researchers and others to get a more holistic view. Drone fishing has economic, political, legal, ecological and physiological implications. Based on this we made some recommendations for further research and monitoring, and shared them with fishing authorities.</p>
<p>The South African Department of Forestry, Fisheries and the Environment then released a <a href="https://www.dffe.gov.za/sites/default/files/legislations/publicnotices/25february2022motorisedequipment_recreationalangling.pdf">public notice</a> warning recreational anglers that the use of drones and other electronic devices is deemed illegal under the <a href="https://www.gov.za/documents/marine-living-resources-act-27-may-1998-0000">South African Marine Living Resources Act</a>.</p>
<p>The fishing drone companies that had already emerged are now struggling to survive. They have taken the department to <a href="https://www.saflii.org/za/cases/ZAGPPHC/2022/250.html">court</a> seeking clarity on the legality of using drones in fishing. The judgement on this case, which is currently in the appeal court, will no doubt pave the way for how drone fishing is managed in South Africa in the future.</p>
<h2>Innovative research methods</h2>
<p>Largely because we were house-bound during the 2020-2021 COVID-19 pandemic we gathered most of our data via the internet. We surveyed social media platforms for drone-fishing dedicated groups and used Google Trends to track internet searches for “drone fishing”.</p>
<p>Results indicated a 357% spike in interest in 2016, after the release of a popular YouTube <a href="https://www.youtube.com/watch?v=8sdUZqOoAq4">video</a> of an angler catching a large longfin tuna from an Australian beach using a drone. The search volume increased to about 3,600 monthly searches from an average of about 1,400 before the peak. “Drone fishing” Facebook groups had over 17,000 members and 38,700 videos with titles including the term “drone fishing” had been uploaded. </p>
<p>The online interest was mostly in three countries: New Zealand, South Africa and Australia. </p>
<p>To get an idea of which fish species were targeted, we then watched 100 YouTube videos posted by drone fishers in those three countries. In both New Zealand and Australia, the most frequently observed catch was red snapper, which is not a species of direct conservation concern. In South Africa, though, sharks made up the majority (97%) of viewed catches, many of which are of severe conservation concern, such as the <a href="https://www.iucnredlist.org/species/3852/2872747">dusky shark</a>. </p>
<h2>Impacts of drone fishing</h2>
<p>Having established interest in and the presence of drone fishing in South Africa, we sought to consider the issue holistically – its impact on:</p>
<ul>
<li><p>targeted fish and their habitats</p></li>
<li><p>other animals in the coastal zone</p></li>
<li><p>other people using the coastal zone.</p></li>
</ul>
<p>Drones with cameras allow anglers to <a href="https://www.instagram.com/reel/Cz8sBz7ihYb/?igshid=MTc4MmM1YmI2Ng%3D%3D">identify</a> ideal fishing habitats far from the shore. Areas that anglers couldn’t reach before are now open to exploitation. Even fish that are released are less likely to survive when caught further offshore. A large fish hooked hundreds of metres offshore is likely to experience <a href="https://www.int-res.com/articles/meps2013/496/m496p207.pdf?">extreme exhaustion and physiological disturbance</a> and may be consumed by other predators. </p>
<p>The potential loss of fishing tackle by drone anglers is also a concern. It is common to lose tackle, either when it gets stuck in rocky habitats or while fighting large fish such as sharks. Both scenarios may result in hundreds of metres of fishing line remaining in the ocean. In addition to polluting the marine environment, such debris threatens to entangle birds, marine mammals and turtles. </p>
<p>In South Africa, drone fishing is only accessible to affluent anglers. Their increased catches might lead to conflict with fishers who depend on their catch for food or income.</p>
<p>It’s also possible that sharing live information on fishing conditions via the internet could add to concerns about the privacy of other public beach users.</p>
<p>Our 2021 <a href="https://link.springer.com/article/10.1007/s13280-021-01578-y#Sec11">paper</a> noted that at the time, there were no specific regulations relating to drone fishing in any country, including South Africa. We drew attention to legislation that could be used indirectly to regulate the practice. </p>
<h2>Regulation and management of fisheries</h2>
<p>Three of the paper’s co-authors were part of a working group for the South African Department of Forestry, Fisheries and the Environment. We shared the paper with the department and in 2022, it took concrete action on this issue for the first time. </p>
<p>The department released a <a href="https://www.dffe.gov.za/sites/default/files/legislations/publicnotices/25february2022motorisedequipment_recreationalangling.pdf">public notice</a> which explicitly prohibits drones and other remotely operated vehicles for angling. </p>
<p>Companies that custom build fishing drones were granted <a href="https://www.gov.za/speeches/use-motorised-equipment-recreational-angling-drones-and-remotely-operated-devices-and-or">leave to appeal</a> the original court ruling on their application to unban drone fishing. The appeal has not yet been heard.</p>
<p>We hope the end result will be better monitoring and management of South African recreational fishery, so that resources are available to those who need them the most.</p><img src="https://counter.theconversation.com/content/218267/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexander Claus Winkler does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Increased interest in recreational fishing with drones has led to concern about its environmental and social impact.Alexander Claus Winkler, Research Associate, Rhodes UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2175982023-11-21T15:13:18Z2023-11-21T15:13:18ZGhana: Akosombo Dam disaster reveals a history of negligence that continues to this day<p>Recent <a href="https://www.linkedin.com/pulse/akosombo-dam-spillage-evidence-climate-pressures-ghana-thecophq-9ceye/">heavy downpours </a>in the Lower Volta area of Ghana led to the <a href="https://www.myjoyonline.com/akosombo-dam-spillage-we-didnt-sleep-on-duty-vra-absolves-itself-of-blame/">worst flooding</a> in the region’s history. The flooding was caused by a <a href="https://www.vra.com/media/2023/Controlled-Spillage-from-the-Akosombo-Dam-and-Kpong-Dam.php">spillage</a> (a deliberate release of water) from the Akosombo Dam, the country’s biggest hydroelectric dam. Over <a href="https://www.ghanaiantimes.com.gh/akosombo-spillage-26000-residents-displaced-by-floods-8000-victims-rescued-inter-ministerial-cttee-tours-affected-areas/">26,000 people</a> were displaced. No deaths have been officially announced. The last recorded spillage was in 2010.</p>
<p>The <a href="https://www.vra.com/about_us/profile.php">Volta River Authority</a>, the state agency that manages the Akosombo Dam, opened the flood gates to release pressure on the dam after unusually high rainfall. By September, Volta Lake, the vast, 400km-long reservoir behind Akosombo Dam, had been filled to capacity. A month after the spillage started, communities along the Volta River were severely affected by the excess water. </p>
<p>Local residents fled to safety, leaving behind most of their belongings. Farms were submerged and crops destroyed. The inventory of stores and businesses in low-lying areas suffered extensive damage. </p>
<p>The director of the disaster management organisation was <a href="https://gna.org.gh/2023/10/flood-in-most-districts-not-due-to-vra-spillage-nadmo/">quoted</a> as saying that the floods were caused by heavy rains in the Volta catchment basin. Climate change and global warming, he explained, were responsible for all the water coming down the Volta. </p>
<p>Other factors are relevant too to understand this crisis. Based on my <a href="https://iupress.org/9780253059956/a-dam-for-africa/">knowledge of the area</a> as a <a href="https://scholar.google.com/citations?hl=en&user=FY41aRUAAAAJ&view_op=list_works&sortby=pubdate">historian</a> who has studied the Akosombo Dam and its impact on the lives of the people in the Lower Volta, I would attribute the extent of the calamity to two additional factors. </p>
<p>One is the ecological and economic changes brought by the construction of the Akosombo Dam. The areas affected by the flooding have been populated by farmers who settled there after they could no longer farm and fish elsewhere in the Lower Volta once the dam was built. The second is the failings of the Volta River Authority which manages the dam.</p>
<h2>The history</h2>
<p>The Lower Volta lies below the country’s two large hydroelectric dams, Akosombo, <a href="https://newafricanmagazine.com/16321/">completed</a> in 1965, and <a href="https://dbpedia.org/page/Kpong_Dam">Kpong</a>, completed in 1982.</p>
<p>The Volta River Project was Ghana’s largest development project. It included Akosombo Dam and an aluminum smelter as the dam’s main beneficiary. Even in the 1950s the planners of the project recognised that damming the Volta would have severe economic effects on the Lower Volta. There was also recognition that the project would lead to major ecological changes.</p>
<p>In its <a href="https://books.google.com/books/about/The_Volta_River_Project_Engineering_repo.html?id=cJSGAAAAIAAJ">1956 report</a>, the preparatory commission, which closely studied the Volta River Project, detailed the changes that were to come. </p>
<p>The first was that the construction of the dam would put an end to the ecological cycle that had nourished the Lower Volta for centuries. The area was accustomed to substantial annual floods that filled hundreds of small creeks, fertilised agricultural lands and created large fisheries. The cycle of annual floods enabled a prosperous agricultural society with farming, fishing and clam picking (which was largely done by women.)</p>
<p>During the dry season, men migrated upstream to fish, hunt, farm and build boats. </p>
<p>Once Akosombo was built, the annual floods stopped. The dam created a regulated river downstream.</p>
<p>The preparatory commission warned about the radical changes the dam would bring downstream. But policymakers and Ghana’s governments ignored them. </p>
<p>The impact on communities of the Lower Volta has been examined by researcher <a href="https://theconversation.com/profiles/dzodzi-tsikata-365479">Dzodzi Tsikata</a> in her study <a href="https://www.amazon.com/Living-Shadow-Large-Dams-Communities/dp/9004141448">Living in the Shadow of the Large Dams</a>. In response to the dam being built many people migrated upstream and formed the fishing communities that now populate the shores of Volta Lake. Those who stayed and continued farming had to adapt their agricultural practices by planting in low-lying areas closer to the Volta River. </p>
<p>Subsequently, settlements expanded into the former flood plains along the river. These areas have now been inundated by the flooding caused by the spillage at Akosombo. </p>
<h2>Woeful response</h2>
<p>The current flooding raises the question of who is responsible and who must compensate those who have been affected. </p>
<p>According to the <a href="https://ghanalegal.com/laws_subdomain/acts/id/72/volta-river-development-act/">1961 Volta River Development Act (Act 46)</a>, the Volta River Authority has a statutory responsibility to prevent Volta Lake from rising to a height of 85.3 metres above sea level and cresting the dam. </p>
<p>In addition, the Volta River Authority should prevent the “flow of water past the dam” from causing “flooding downstream from dam above the levels which were normal” prior to the construction of Akosombo. </p>
<p>Finally, the authority has to “take reasonable measures to give warning of possible flooding from the lake or from the River Volta downstream from the dam.” </p>
<p>The Volta River Authority preserved the integrity of the Akosombo Dam by opening the floodgates and spilling the lake’s excess water. But it failed in its other tasks. </p>
<ul>
<li><p>It did not maintain an unoccupied flood zone which could absorb the excess water. </p></li>
<li><p>It failed to give people a timely warning to evacuate. The managers of the dam organised a simulation exercise for surrounding communities in May 2023.</p></li>
<li><p>It did not help people in the flood zones to move out of danger with their belongings.</p></li>
</ul>
<p>In my view, the Volta River Authority, and by extension the Ghanaian state, have a moral obligation to compensate the people affected by the spillage and the subsequent floods. </p>
<p>Although the authority has income through the sale of electricity, it <a href="https://www.vra.com/resources/annual_reports/2022%20VRA%20Group%20Audited%20Annual%20Reports%20and%20Financial%20Statements.pdf">operated at a loss</a> in 2022, due to increased administrative expenses triggered by inflation. The Ghanaian state is also <a href="https://www.aljazeera.com/features/2023/10/5/lack-of-safety-nets-hurt-ghanas-most-vulnerable-as-economic-woes-deepen">facing deficits</a>. So there is little certainty about whether the residents of the Lower Volta will receive compensation. </p>
<p>One would hope that the Volta River Authority and the Ghanaian state would finally address some of the historical injustice experienced by the communities in the Lower Volta since the early 1960s.</p><img src="https://counter.theconversation.com/content/217598/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephan Miescher does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Communities along the bank of the dam have been victims of injustice since the early 1960s.Stephan Miescher, Professor of History, University of California, Santa BarbaraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2170252023-11-13T21:44:00Z2023-11-13T21:44:00ZGulf of St. Lawrence: Analyzing fish blood can show us how healthy they are<figure><img src="https://images.theconversation.com/files/557461/original/file-20231003-21-bibw4p.jpeg?ixlib=rb-1.1.0&rect=30%2C12%2C3995%2C3005&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The industrialization of the fishing industry and changes in the environment have raised many issues about the management of our fisheries.</span> <span class="attribution"><span class="source">(Fanny Fronton)</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>The Gulf of St. Lawrence is an invaluable resource for Canada. Fish and shellfish fisheries that date to the 16th century have remained an essential source of income for many communities, including those on the North Shore and Gaspésie or the Îles-de-la-Madeleine.</p>
<p>For example, in <a href="https://publications.gc.ca/collections/collection_2019/mpo-dfo/Fs124-10-2018-eng.pdf">Îles-de-la-Madeleine</a>, nearly 1,800 jobs (for a total of 12,500 inhabitants) were linked to fishing in 2015.</p>
<p>But the industrialization of fishing, and changes in the environment, have brought about many new problems in the management of our fisheries. The abundance of different fish species in the Gulf has fluctuated greatly over the last 20 years.</p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469058/original/file-20220615-9549-jj1phn.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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</figure>
<p><em>This article is part of our series, <a href="https://theconversation.com/ca-fr/topics/fleuve-saint-laurent-116908">The St. Lawrence River: In depth</a>.
Don’t miss new articles on this mythical river of remarkable beauty. Our experts look at its fauna, flora and history, and the issues it faces. This series is brought to you by <a href="https://theconversation.com/ca-fr">La Conversation</a>.</em></p>
<hr>
<p>A case in point: the number of Greenland halibut has declined drastically. This year, <a href="https://www.hi.no/hi/nettrapporter/imr-pinro-en-2023-6">landings</a> are six times lower for fishermen compared to last year.</p>
<p>But other species are benefiting from the situation. This is the case for the population of Atlantic halibut, which is at record levels today.</p>
<p>What is causing these changes? And can we predict further changes?</p>
<p>As a doctoral student in biology at the Institut national de la recherche scientifique (INRS), I am trying to find possible answers to these questions as part of my research work.</p>
<h2>A new health monitoring technique</h2>
<p>The means available for studying the health of fish at the individual level are limited. On the one hand, we can calculate indicators from the weight and height of individual fish. But these measurements are too vague and don’t tell us much.</p>
<p>The logistics of performing biopsies on the tissue of fish — which requires taking samples from their muscle or organs — are complex. To carry them out, researchers must have to travel to the ocean, physically collect samples and bring them back to a laboratory. And then there are ethical considerations, since obviously fish must be sacrificed to achieve this.</p>
<p>Even so, these methods are not very effective for detecting stress induced by environmental changes, and are not effective for detecting stress at early stages, before the physical effects can become manifest.</p>
<p>Yet in a context where the abundance of certain fish species is in rapid decline, an analysis of their overall health is necessary. Fortunately, a new tool is being developed: the <a href="https://www.nature.com/articles/s41598-023-32690-6">circulating microbiome</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="viruses in the blood" src="https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=431&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=431&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551779/original/file-20231003-15-6ou9xh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=431&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It is often wrongly believed that blood is sterile.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>A little-known practice</h2>
<p>The circulating microbiome is a biomarker, an alarm signal that can be detected in fish even before their health begins to deteriorate. A good biomarker is sensitive, easy to sample, and inexpensive.</p>
<p>The analysis of the circulating microbiome, made up of the DNA of bacteria found in the blood, is directly inspired by <a href="https://theconversation.com/ladn-%20circulating-a-new-simple-and-rapid-weapon-in-the-diagnosis-and-monitoring-of-cancers-206786">similar analyses performed on humans</a>, which provide a great deal of information.</p>
<p>In particular, these analyses make it possible to detect anomalies resulting from the effect of a stress factor on the body, or the development of a disease.</p>
<p>Changes in the environment can also be detected from studying the circulating microbiome. But a major problem emerges here: a fish is not a human. Humans are studied in such detail that knowledge about their health can then be used for an infinite amount of further research. However, sampling fish blood is not a common practice. So there is a great deal that needs to be done before we can properly evaluate the health of fish.</p>
<p>Since the analysis of the circulating microbiome in fish has never been studied before, a lot of work needs to be done to develop the technique.</p>
<h2>Traces of bacteria in the blood?</h2>
<p>As blood circulates throughout the body, it comes into contact specifically with bacteria that make up the other microbiomes (intestinal, oral, dermal). Both in fish and humans, these bacteria are essential for good health.</p>
<p>When we analyze bacterial DNA in the blood, it is therefore possible to find bacteria from the intestine, mouth, or skin. But the hypothesis that these are bacteria specific to the blood cannot be completely ruled out either.</p>
<p>While some continue to believe that blood is sterile, and therefore does not contain any bacteria, we have known since the 1970s that this hypothesis is false — it was confirmed <a href="https://doi.org/10.1128/jcm.39.5.1956-1959.2001">in the 2000s by genomic studies</a>. It’s possible that in 1674, the Dutch microbiologist Antonie Van Leeuwenhoek may even have observed bacteria in salmon blood <a href="https://doi.org/10.3389/fcimb.2019.00148">under a microscope</a>.</p>
<p>Today, we can analyze these bacteria in detail by targeting a very specific bacterial gene, the 16S ribosomal RNA gene. Present in all bacteria around the world, this gene varies slightly from one species to another. That makes it possible to identify and analyze the biodiversity of the microbiome.</p>
<h2>I eat, therefore I am</h2>
<p>Our recent work has made it possible to characterize, for the first time, the <a href="https://www.nature.com/articles/s41598-023-32690-6">circulating microbiomes of turbot and halibut</a>. We have demonstrated that the two fish species have circulating microbiomes dominated by the presence of the species <em>Pseudoalteromonas</em> and <em>Psychrobacter</em>. These bacteria are known to colonize cold environments, for example the bottom of the Gulf of St. Lawrence, which is around 5°C. They are also known to produce bioactive compounds (antibacterials and antifungals). They are more tenacious than other bacteria.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="person with blue gloves holds a fish" src="https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551768/original/file-20231003-29-qhulgz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Greenland halibut.</span>
<span class="attribution"><span class="source">(Fanny Fronton)</span>, <span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<p>However, differences can be observed between the two species. Turbot has more bacteria called <em>Vibrio</em>, some of which metabolize chitin, a molecule that makes up the shells of the invertebrates on which it feeds. Atlantic halibut, for its part, presents more <em>Acinetobacter</em> bacteria, typical of piscivorous (fish-eating) diets in the intestinal microbiomes. The circulating microbiome in these two fish species therefore seems to be influenced by intestinal bacteria, as is the case in humans. We could therefore potentially link a blood microbiome to the fish’s diet, which is often difficult to estimate.</p>
<h2>An embryonic, but promising technique</h2>
<p>So this first bacterial mapping of the blood of these two species probably reflects their respective intestinal microbiome. From this characterization, detection of a variation in the composition of bacteria could be linked to stress, a change in the environment or a physiological change in the animal.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="comic strip" src="https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=907&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=907&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=907&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1140&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1140&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540859/original/file-20230802-23891-ctgz3u.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1140&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Comic strip illustrating the principle of analyzing the circulating microbiome.</span>
<span class="attribution"><span class="source">(Fanny Fronton)</span>, <span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<p>For example, we know that in humans, the loss of <em>Actinobacteria</em> in the circulating microbiome is associated with severe acute <a href="https://doi.org/10.3389/fcimb.2018.00005">pancreatitis</a>. And there are dozens of examples like this in humans.</p>
<p>This study, the result of a collaboration between university researchers from INRS, the University of Québec at Rimouski and the Department of Fisheries and Oceans Canada, provides a small overview of the informative potential offered by the blood microbiomes of fish from the Gulf of St. Lawrence.</p>
<p>Further research will make it possible to estimate their health and better predict the evolution of their population. The dramatic collapse of the cod stock in the late 1980s had a major impact on fishermen. Several of them even fear that this situation will happen again with another species. As turbot remains a species at risk, it is essential to ensure better management of St. Lawrence species.</p>
<p>Only by refining our analysis techniques and deepening our scientific knowledge can we prevent this type of collapse from happening again in the future.</p><img src="https://counter.theconversation.com/content/217025/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Fanny Fronton received a grant from the Fondation Armand Frappier.</span></em></p>Blood isn’t sterile, and analyzing the bacteria in it could help assess the health of fish and prevent the collapse of their populations.Fanny Fronton, Doctorante en Écologie halieutique et biologie moléculaire, Institut national de la recherche scientifique (INRS)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2145982023-10-30T16:16:45Z2023-10-30T16:16:45ZNiger delta is rich in resources, but environmental destruction is pushing people into poverty<p>Nigeria’s Niger Delta region is rich in natural resources. Its <a href="https://www.researchgate.net/publication/284727294_Review_of_Ecological_Effects_of_Oil_Exploration_in_the_Niger-Delta_Nigeria">vast oil and gas deposits</a> are the mainstay of the country’s economy. </p>
<p>The region, in the southernmost part of the country, features coastal barrier islands, mangroves, freshwater swamp forests and lowland rain forests. The coast offers various ways of making a living, like fishing, tourism, producing salt, and farming coconut and bananas. </p>
<p>Yet it is estimated that over 47% of the population in the region <a href="https://beamexchange.org/uploads/filer_public/73/ff/73ffbabd-2447-4924-8a85-0a43f6f266dc/made-nigeria-poverty-assessment-report-final_compressed.pdf#page=4">lives</a> below the poverty line. </p>
<p>We study the economic aspects of environmental issues, and in a recent <a href="https://www.researchgate.net/profile/Otekenari-Elisha/publication/353741948_DESTRUCTION_OF_COASTAL_ECOSYSTEMS_AND_THE_VICIOUS_CYCLE_OF_POVERTY_IN_NIGER_DELTA_REGION/links/610d9423169a1a0103e569f4/DESTRUCTION-OF-COASTAL-ECOSYSTEMS-AND-THE-VICIOUS-CYCLE-OF-POVERTY-IN-NIGER-DELTA-REGION.pdf">paper</a> set out to understand the relationship between the destruction of coastal ecosystems in this region and the economic hardship the people faced.</p>
<p>We found that marine ecosystems had been badly affected by a number of factors, including an increasing population, pollution, over-fishing, damaging fishing techniques and global warming.</p>
<p>The degradation of the environment affects the poor the most as they depend on natural resources like seafood and wood for survival and energy. And they do not earn enough to relocate from polluted areas. </p>
<h2>The destruction of an ecosystem</h2>
<p>We identified a few areas where the Niger Delta ecosystem had been badly affected. The environmental problems in communities like Bille, Andoni, Okirika, Emohua and Ibaa in Rivers State are caused by oil spills, gas flaring, human activities and water pollution, among others. </p>
<p>Between 1976 and 2006, there were at least <a href="http://large.stanford.edu/courses/2017/ph240/nwagbo1/">7,000 oil spills</a> in the region, affecting an area of more than 2,500 square kilometres. These oil spills have polluted the soil, water and air, and they have had a <a href="https://www.aljazeera.com/features/2022/9/9/niger-delta-oil-spills-bring-poverty-low-crop-yields-to-farmers">devastating impact</a> on the people who live in the region. The destruction of the ecosystem has led to environmental problems like flooding and soil erosion, which destroys homes and crops, leading to further poverty. The lack of a healthy ecosystem has led to <a href="https://www.sciencedirect.com/science/article/abs/pii/S0013935121000190#:%7E:text=Lung%20and%20skin%20cancers%20are,et%20al.%2C%202015">health problems</a> for the people living in the region. </p>
<p>Gas flaring is the process of burning off excess natural gas that is produced during oil drilling. More than 2.5 billion cubic feet of natural gas are <a href="https://www.amisdelaterre.org/wp-content/uploads/2019/10/gas-flaring-nigeria.pdf#page=4">flared</a> every day in the Niger Delta. This process <a href="https://www.iea.org/energy-system/fossil-fuels/gas-flaring">emits greenhouse gases</a> and other pollutants into the atmosphere, and it also wastes a valuable resource that could be used to generate electricity or heat homes.</p>
<p>Mangroves are being lost <a href="https://www.researchgate.net/profile/Otekenari-Elisha/publication/366371709_Asian_Journal_of_Current_Research_COMMUNITY-BASED_INTERVENTION_IN_THE_CONTROL_OF_ARTISANAL_REFINING_AGAINST_THE_ENVIRONMENT_IN_NIGER_DELTA_REGION_NIGERIA/links/639d793e095a6a77743755d0/Asian-Journal-of-Current-Research-COMMUNITY-BASED-INTERVENTION-IN-THE-CONTROL-OF-ARTISANAL-REFINING-AGAINST-THE-ENVIRONMENT-IN-NIGER-DELTA-REGION-NIGERIA.pdf#page=8">because of water pollution</a>. Mangrove forests are an important source of food and income for local communities, and their loss has led to a decline in fish stocks and other marine resources. This has damaged the livelihoods of fishers and increased the price of fish in local markets. </p>
<p>The environmental consequences of the destruction of mangroves include erosion and increased vulnerability to storms and flooding.</p>
<p>Natural resources such as nutrient-rich soil, water, trees and fossil fuels abound in marine ecosystems. Excessive exploitation of these resources through mining, logging and oil drilling has had a negative impact.</p>
<p>Animals in an ecosystem keep the food chain in balance. Due to overfishing and hunting, many animals are disappearing from the Niger Delta. Manatees, sea turtles, dolphins, monkeys, antelope and others are under threat. </p>
<p>The destruction of the ecosystem in the Niger Delta has led to a cycle of poverty:</p>
<ul>
<li><p>depletion of resources means people can’t make a living</p></li>
<li><p>environmental problems like flooding and soil erosion destroy homes and crops</p></li>
<li><p>human health depends on a healthy ecosystem.</p></li>
</ul>
<p>There is <a href="https://www.es.amnesty.org/fileadmin/noticias/Niger_Delta_Campaign_Digest_01.pdf">evidence</a> that destruction of the ecosystem has led to poverty in the Niger Delta region. Increasing soil sterility and diminishing agricultural output have <a href="https://www.researchgate.net/profile/Otekenari-Elisha/publication/353741948_DESTRUCTION_OF_COASTAL_ECOSYSTEMS_AND_THE_VICIOUS_CYCLE_OF_POVERTY_IN_NIGER_DELTA_REGION/links/610d9423169a1a0103e569f4/DESTRUCTION-OF-COASTAL-ECOSYSTEMS-AND-THE-VICIOUS-CYCLE-OF-POVERTY-IN-NIGER-DELTA-REGION.pdf#page=10">forced</a> farmers to move or seek illicit sources of living. The degradation of traditional fishing grounds has worsened hunger and poverty in fishing communities.</p>
<h2>Protecting and restoring ecosystems</h2>
<p>The impact of environmental degradation will only worsen if nothing is done to protect and restore degraded ecosystems.</p>
<p>In our paper we made the following suggestions.</p>
<ul>
<li><p>Regulate human activities: Fishing and hunting in the region should be controlled to prevent the depletion of fish and wildlife. Industrial activities, such as oil drilling and shipping, should also be regulated to prevent further pollution of the air, water and soil.</p></li>
<li><p>Restore degraded ecosystems: Mangrove forests can be replanted in areas where they have been destroyed. Another example is restoring wildlife populations through captive breeding programmes and releasing animals back into their natural habitats.</p></li>
<li><p>Build the capacity of local communities to manage their natural resources: This is essential for the long-term protection of the region. One example is providing training to community members on sustainable fishing and hunting practices. Another example is giving local communities a say in how their natural resources are managed.</p></li>
<li><p>Establish marine protected areas: This would help to conserve marine life and ensure that coastal communities can continue to benefit from the resources they depend on. One example is the Calabar-Oron Marine Protected Area in Cross River and Akwa Ibom states. It is home to a variety of marine life, including dolphins, turtles and whales. The area is used for sustainable fishing, ecotourism and research.</p></li>
</ul>
<p>We also recommend steps to address the root causes of poverty and inequality.</p>
<ul>
<li><p>Provide access to quality education and healthcare: Education can help to create greater awareness about environmental issues, and lead to economic opportunities. Availability of these social services could reduce the appeal of rebel groups that promise economic and social benefits.</p></li>
<li><p>Address marginalisation: Groups like women and ethnic minorities can be given equal access to resources and opportunities through inclusive decision-making at the local, state and national levels. Development programmes should target their specific needs. </p></li>
</ul>
<p>Finally, renewed efforts should be made to address conflict and insecurity in the Niger Delta by strengthening governance and the rule of law. Improved governance can lead to stronger enforcement of environmental laws and regulations, which can protect ecosystems from further degradation. In addition, it can protect land rights and create a more stable environment that offers economic opportunities.</p><img src="https://counter.theconversation.com/content/214598/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Otekenari David Elisha does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Environmental degradation of Nigeria’s Niger Delta region is causing poverty as well as food insecurity, increased crime and conflict.Otekenari David Elisha, Environmental Economist, Ignatius Ajuru University of Education Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2155292023-10-17T19:08:11Z2023-10-17T19:08:11ZMore than 200 scientists from 19 countries want to tell us the Southern Ocean is in trouble<figure><img src="https://images.theconversation.com/files/554159/original/file-20231017-15-ht1j0s.jpg?ixlib=rb-1.1.0&rect=28%2C4%2C3155%2C2110&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Pat James, Australian Antarctic Division</span></span></figcaption></figure><p>While the Southern Ocean around Antarctica has been <a href="https://theconversation.com/the-southern-ocean-absorbs-more-heat-than-any-other-ocean-on-earth-and-the-impacts-will-be-felt-for-generations-189561">warming for decades</a>, the annual extent of winter sea ice seemed relatively stable – compared to the Arctic. In some areas Antarctic sea ice was even increasing. </p>
<p>That was until 2016, when <a href="https://www.nature.com/articles/s43247-023-00961-9">everything changed</a>. The annual extent of winter sea ice stopped increasing. Now we have had <a href="https://theconversation.com/devastatingly-low-antarctic-sea-ice-may-be-the-new-abnormal-study-warns-212376">two years of record lows</a>.</p>
<p>In 2018 the international scientific community agreed to produce the first marine ecosystem assessment for the Southern Ocean. We modelled the assessment process on a working group of the Intergovernmental Panel on Climate Change (IPCC). So the resulting “<a href="https://zenodo.org/records/8359585">summary for policymakers</a>” being released today is like an IPCC report for the Southern Ocean. </p>
<p>This report can now be used to guide decision-making for the protection and conservation of this vital region and the diversity of life it contains. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing the number of authors from different regions, illustrating the international nature of the assessment process." src="https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=271&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=271&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=271&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=341&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=341&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554187/original/file-20231017-2786-gzvb0u.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=341&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Global participation (numbers of authors from different regions) in the assessment.</span>
<span class="attribution"><a class="source" href="https://zenodo.org/records/8359585">Constable, A.J. et al (2023) Marine Ecosystem Assessment for the Southern Ocean.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fractured-foundations-how-antarcticas-landfast-ice-is-dwindling-and-why-thats-bad-news-207814">Fractured foundations: how Antarctica's 'landfast' ice is dwindling and why that's bad news</a>
</strong>
</em>
</p>
<hr>
<h2>Why should we care about sea ice?</h2>
<p>Sea ice is to life in the Southern Ocean as soil is to a forest. It is the foundation for Antarctic marine ecosystems.</p>
<p>Less sea ice is a danger to all wildlife – from krill to emperor penguins and whales.</p>
<p>The sea ice zone provides essential food and safe-keeping to young Antarctic krill and small fish, and seeds the expansive growth of phytoplankton in spring, nourishing the entire food web. It is a platform upon which penguins breed, seals rest, and around which whales feed. </p>
<p>The international bodies that manage Antarctica and the Southern Ocean under the <a href="https://www.ats.aq/index_e.html">Antarctic Treaty System</a> urgently need better information on marine ecosystems. Our report helps fill this gap by systematically identifying options for managers to maximise the resilience of Southern Ocean ecosystems in a changing world.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1705569410604314758"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/emperor-penguins-face-a-bleak-future-but-some-colonies-will-do-better-than-others-in-diverse-sea-ice-conditions-214625">Emperor penguins face a bleak future – but some colonies will do better than others in diverse sea-ice conditions</a>
</strong>
</em>
</p>
<hr>
<h2>An open and collaborative process</h2>
<p>We sought input from a wide range of people across the entire Southern Ocean science community. </p>
<p>We sought to answer questions about the state of the whole Southern Ocean system - with an eye on the past, present and future.</p>
<p>Our team comprised 205 authors from 19 countries. They authored <a href="https://www.frontiersin.org/research-topics/10606/marine-ecosystem-assessment-for-the-southern-ocean-meeting-the-challenge-for-conserving-earth-ecosystems-in-the-long-term#overview">24 peer-reviewed papers</a>. We then distilled the findings from these papers into our summmary for policymakers. </p>
<p>We deliberately modelled the multi-disciplinary assessment process on a working group of the IPCC to distill the science into an easy-to-read and concise narrative for politicians and the general public alike. It provides a community assessment of levels of certainty around what we know.</p>
<p>We hope this “sea change” summary sets a new benchmark for translating marine research into policy responses. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graphic illustrating how the system-level assessment of marine ecosystems came together, showing a group of people at a table with concentric circles in the background including observations, drivers of change and ecosystem services" src="https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=749&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=749&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=749&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=942&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=942&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554169/original/file-20231017-15-6w52ns.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=942&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Our system-level assessment addressed the multiple drivers of ecosystem change in the Southern Ocean.</span>
<span class="attribution"><a class="source" href="https://zenodo.org/records/8359585">Constable, A.J. et al (2023) Marine Ecosystem Assessment for the Southern Ocean.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<h2>So what’s in the report?</h2>
<p>Southern Ocean habitats, from the ice at the surface to the bottom of the deep sea, are changing. The warming of the ocean, decline in sea ice, melting of glaciers, collapse of ice shelves, changes in acidity, and direct human activities such as fishing, are all impacting different parts of the ocean and their inhabitants.</p>
<p>These organisms, <a href="https://theconversation.com/an-ocean-like-no-other-the-southern-oceans-ecological-richness-and-significance-for-global-climate-151084">from microscopic plants to whales</a>, face a changing and challenging future. Important foundation species such as Antarctic krill are likely to decline with consequences for the whole ecosystem.</p>
<p>The assessment stresses climate change is the most significant driver of species and ecosystem change in the Southern Ocean and coastal Antarctica. It calls for urgent action to curb global heating and ocean acidification.</p>
<p>It reveals an urgent need for international investment in <a href="https://theconversation.com/we-landed-a-camera-on-venus-before-seeing-parts-of-our-own-oceans-its-time-to-ramp-up-observations-closer-to-home-212970">sustained, year-round and ocean-wide</a> scientific assessment and observations of the health of the ocean. </p>
<p>We also need to develop better integrated models of how individual changes in species along with human impacts will translate to system-level change in the different food webs, communities and species.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1711094111305089149"}"></div></p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/antarcticas-heart-of-ice-has-skipped-a-beat-time-to-take-our-medicine-202729">Antarctica's heart of ice has skipped a beat. Time to take our medicine</a>
</strong>
</em>
</p>
<hr>
<h2>What’s next?</h2>
<p>Our report will be tabled at <a href="https://meetings.ccamlr.org/en">this week’s international meeting</a> of the Commission for the Conservation of Antarctic Marine Living Resources in Hobart.</p>
<p>The commission is the international body responsible for the conservation of marine ecosystems in the Southern Ocean, with membership of 26 nations and the European Union.</p>
<p>It is but one of the bodies our new report can assist. Currently assessments of change in habitats, species and food webs in the Southern Ocean are compiled separately for at least ten different international organisations or processes.</p>
<p>The Southern Ocean is a crucial life-support system, not just for Antarctica but for the entire planet. So many other bodies will need the information we produced for decision-making in this critical decade for action on climate, including the IPCC itself.</p>
<p>Beyond the science, the assessment team has delivered important lessons about how coordinated, collaborative and consultative approaches can deliver ecosystem information into policymaking. Our first assessment has taken five years, but this is just the beginning. Now we’re up and running, we can continue to support evidence-based conservation of Southern Ocean ecosystems into the future. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/record-low-antarctic-sea-ice-is-another-alarming-sign-the-oceans-role-as-climate-regulator-is-changing-204680">Record low Antarctic sea ice is another alarming sign the ocean's role as climate regulator is changing</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/215529/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew J Constable has worked for the Australian Public Service in the Australian Antarctic Division, received funding from Pew Charitable Trusts, and, for the marine ecosystem assessment for the Southern Ocean, he received funding from environmental and fisheries non-government organisations (details are identified in the Summary for Policy Makers).</span></em></p><p class="fine-print"><em><span>Jess Melbourne-Thomas receives funding from the Climate Systems Hub of the Australian Government’s National Environmental Science Program, and the Fisheries Research and Development Corporation.</span></em></p>The first comprehensive assessment of trends in Southern Ocean ecosystems reveals an urgent need to address climate change. The summary for policymakers can guide decision-makers.Andrew J Constable, Adviser, Antarctica and Marine Systems, Science & Policy, University of TasmaniaJess Melbourne-Thomas, Transdisciplinary Researcher & Knowledge Broker, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2132582023-10-16T01:38:40Z2023-10-16T01:38:40ZCritically endangered scalloped hammerheads gather in seas off Perth. They need protection<figure><img src="https://images.theconversation.com/files/553890/original/file-20231016-18-xqswws.jpg?ixlib=rb-1.1.0&rect=0%2C26%2C5991%2C3979&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Unlike nearly every other species of shark, scalloped hammerheads are highly social. They gather in large groups, or aggregations, numbering in the hundreds. But why? We don’t know. </p>
<p>With the help of drones, we now know a bit more. In our <a href="https://doi.org/10.1093/icesjms/fsad153">new research</a>, we describe finding a location in a marine park off the coast of Perth where juvenile scalloped hammerheads (<em>Sphyrna lewini</em>) gather in numbers. </p>
<p>Scalloped hammerheads – one of ten species in the hammerhead family – prefer warm waters. But they have become regular visitors to the waters off Perth in summer, now the <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/aec.13149">southernmost part</a> of their range. The sharks are not considered dangerous to humans. </p>
<p>These iconic sharks are among the world’s <a href="https://www.iucnredlist.org/species/39385/2918526">most threatened species</a> due to over-fishing. And incredibly they are still legally fished in <a href="https://www.abc.net.au/news/2022-03-28/nt-hammerhead-sharks-tighter-fishing-rules/100930138">Australia</a>, despite their populations falling by 80% in just 55 years. </p>
<p>They are in danger unless we protect them. </p>
<h2>What’s special about these oceanic wayfarers?</h2>
<p><a href="https://www.fishbase.se/summary/912#:%7E:text=This%20hammerhead%20shark%20is%20distinguished,posterior%20to%20or%20nearly%20opposite">Scalloped hammerheads</a> are named for the dents on their hammer-shaped head or <a href="https://theconversation.com/why-do-hammerhead-sharks-have-hammer-shaped-heads-184372">cephalofoil</a>. They’re skilled long-distance swimmers and exceptional <a href="https://www.science.org/doi/10.1126/science.add4445#:%7E:text=Scalloped%20hammerhead%20sharks%20occupy%20warm,diets%20(12%E2%80%9318).">free divers</a>, able to hunt in the dark waters 500 metres below the surface. They grow slowly and live for up to 55 years. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-do-hammerhead-sharks-have-hammer-shaped-heads-184372">Why do hammerhead sharks have hammer-shaped heads?</a>
</strong>
</em>
</p>
<hr>
<p>They’re a challenging species to study because they cover long distances and spend lots of time down deep. Finding a place where these sharks regularly aggregate offers us a remarkable opportunity to learn more about these oceanic wayfarers.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&rect=0%2C2%2C1917%2C1074&q=45&auto=format&w=1000&fit=clip"><img alt="A school of scalloped hammerhead sharks in shallow seas" src="https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&rect=0%2C2%2C1917%2C1074&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/553422/original/file-20231012-21-jof197.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">From our drones, we could watch as the scalloped hammerheads grouped together each month.</span>
<span class="attribution"><span class="source">Author provided</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>How did we find them?</h2>
<p>Small commercial drones <a href="https://www.mdpi.com/2504-446X/5/1/8">are revolutionising</a> the way we study marine wildlife – especially sharks. The aerial perspective lets us see things we couldn’t see before. Drones have shed light on <a href="https://theconversation.com/humpback-whales-have-been-spotted-bubble-net-feeding-for-the-first-time-in-australia-and-we-have-it-on-camera-157355">elusive behaviours</a> we have otherwise been unable to verify. Footage can also be used to identify, count and measure animals.</p>
<p>We heard surf lifesavers had observed hammerhead sharks off Perth beaches during their helicopter shark patrols. We began our search at the <a href="https://exploreparks.dbca.wa.gov.au/park/shoalwater-islands-marine-park">Shoalwater Islands Marine Park</a>, off the coast from Rockingham, in Perth’s southern suburbs. </p>
<p>Over two successive summers, we used drones to successfully spot and then track scalloped hammerheads as they aggregated inside the marine park. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photo of Perth's shoalwater islands marine park. Image shows shallow waters, land and sand" src="https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=275&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=275&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=275&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=345&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=345&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551983/original/file-20231004-21-xyon8b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=345&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The juvenile sharks aggregate in the shallow waters of the Shoalwater Islands Marine Park, south of Perth.</span>
<span class="attribution"><span class="source">Author provided</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>What did we learn?</h2>
<p>We learned many things. First, the scalloped hammerheads aggregating at the marine park were juveniles, not adults. </p>
<p>We only found them in a small area of the marine park. They were present with the full moon. </p>
<p>Once aggregated, they would swim in formation, moving in winding patterns through the shallow waters of the marine park. </p>
<p>In terms of what were they doing, our study suggest they’re seeking a place to rest and recover. Sharks often hunt more on the nights with a full moon, taking advantage of better light to see prey. </p>
<p>That would mean these juveniles are tired after a night’s hunting. Now they need to rest and digest. Gathering in a group could also provide some degree of protection from other predators in the area. </p>
<p>It’s likely, therefore, these shallow waters are important shelter for scalloped hammerheads.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of a scalloped hammerhead shark filmed by a robotic camera underwater" src="https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=340&fit=crop&dpr=1 600w, https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=340&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=340&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=427&fit=crop&dpr=1 754w, https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=427&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/551982/original/file-20231004-27-gnonhe.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=427&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This scalloped hammerhead was filmed by a baited remote underwater video system (BRUVS) off the Cocos Keeling Islands, Western Australia.</span>
<span class="attribution"><span class="source">Author provided</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>How can we protect them?</h2>
<p>Our research points to the urgent need to strengthen protection of scalloped hammerheads in the popular Shoalwater Islands Marine Park. </p>
<p>We need a code of conduct to prevent water users such as boaters, kayakers, and swimmers from disturbing the animals, similar to those protecting <a href="https://ningaloo-atlas.org.au/node/371">whale sharks</a> and <a href="https://www.agriculture.gov.au/sites/default/files/documents/aust-national-guidelines-whale-dolphin-watching-2017.pdf">humpback whales</a>. Boat speed limits and bans on chasing animals are essential if we are to protect these endangered animals.</p>
<p>Stopping fishing at the aggregation site is vitally important. Hammerheads are <a href="https://www.int-res.com/articles/meps2013/496/m496p207.pdf">extremely vulnerable to any capture</a> and are unlikely to survive “catch and release” fishing. The marine park should be a safe spot for the sharks to shelter and rest.</p>
<p>We need to strengthen protections in the marine park, shifting from multiple use status – which allows fishing – to highly protected, which prohibits fishing. </p>
<p>Right now, the federal government is reviewing the status of these sharks. Given ongoing fishing pressure, there are clear reasons to assess them as endangered rather than their unclear status as “<a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=85267">conservation dependent</a>”.</p>
<p>Australia is fortunate to host remarkable and endangered species such as hammerhead sharks. As our understanding grows, so does our responsibility. There are simple steps available to the state and federal government to safeguard the future of this threatened species and maintain healthy marine ecosystems. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/some-sharks-have-declined-by-92-in-the-past-half-century-off-queenslands-coast-108742">Some sharks have declined by 92% in the past half-century off Queensland's coast</a>
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<img src="https://counter.theconversation.com/content/213258/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Naima Andrea López received funding for her PhD research from the Australian Government RTP Scholarship, The Jock Clough Marine Foundation through the Oceans Institute Robson and Robertson Award and The Holsworth Wildlife Research Endowment & The Ecological Society of Australia. </span></em></p><p class="fine-print"><em><span>Jessica Meeuwig does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Scalloped hammerheads pose no risk to us – but we pose enormous risk to them. Our discovery of a large new aggregation gives us an opportunity to protect these animals.Naima Andrea López, Postdoctoral Research Fellow, The University of Western AustraliaJessica Meeuwig, Wen Family Chair in Conservation, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2144222023-10-11T13:15:44Z2023-10-11T13:15:44ZNew treaty to protect the world’s oceans may hurt vulnerable African fisheries<p>Following two decades of fierce negotiations, over 60 countries recently signed a UN <a href="https://www.reuters.com/business/environment/dozens-nations-sign-un-ocean-treaty-implementation-still-awaits-2023-09-20/">Ocean Treaty</a> to conserve biodiversity on the high seas. </p>
<p>The “<a href="https://www.oceanexplorer.noaa.gov/facts/high-seas-governance.html">high seas</a>” are all ocean areas which aren’t under a specific country’s direct ownership or regulation. They make up <a href="https://www.nature.com/articles/d41586-018-05079-z">two-thirds</a> of Earth’s oceans, providing 90% of the habitat available for life. </p>
<p>The <a href="https://documents-dds-ny.un.org/doc/UNDOC/LTD/N23/177/28/PDF/N2317728.pdf?OpenElement">treaty</a> has been celebrated as <a href="https://oceans-and-fisheries.ec.europa.eu/news/historic-achievement-treaty-high-seas-adopted-2023-06-19_en#:%7E:text=Today%2C%20the%20Treaty%20of%20the,loss%20in%20the%20high%20seas.">historic</a>. It’s the first time that action will be taken against unregulated use of resources in this ungoverned space. </p>
<p>It’s <a href="https://unctad.org/news/90-fish-stocks-are-used-fisheries-subsidies-must-stop">estimated</a> that 90% of the world’s marine fish stocks are now fully exploited, overexploited or depleted. Although less than <a href="https://e360.yale.edu/features/a-global-ban-on-fishing-on-the-high-seas-the-time-is-now#:%7E:text=Pauly%3A%20Well%2C%20it%20will%20be,outside%20of%20Exclusive%20Economic%20Zones.">10%</a> of the total global fish catch is from the high seas, the unregulated nature of fishing there has a <a href="https://wwfeu.awsassets.panda.org/downloads/wwftmt_unregulated_fishing_on_the_high_seas_of_the_indian_ocean_2020.pdf">harmful impact</a> on marine life. </p>
<p>The treaty consists of <a href="https://bbnj-mgr.fas.harvard.edu/bbnj-treaty#:%7E:text=On%2019%20June%202023%2C%20nearly%20200%20countries%20adopted,Preamble%2C%2012%20Parts%2C%2076%20Articles%2C%20and%202%20Annexes.">76 articles</a>. Their goals include the protection and sustainable management of the marine environment, preserving the integrity of ocean ecosystems – such as <a href="https://education.nationalgeographic.org/resource/coral-reefs/">coral reefs</a> – and conserving biological diversity. Once ratified, the treaty will allow the establishment of <a href="https://oceans-and-fisheries.ec.europa.eu/news/win-ocean-high-seas-treaty-signed-united-nations-2023-09-20_en">marine protected areas</a> in the high seas.</p>
<p>Though it doesn’t explicitly prohibit commercial fishing in the high seas, it includes language that may allow for their “sustainable use”. So, the establishment of a protected area in the high seas is expected to address unsustainable fishing activities in the space, but only if <a href="https://www.nature.com/articles/s44183-023-00013-x#:%7E:text=The%20new%20Treaty%20lays%20out,high%20seas%2C%20among%20other%20things.">fully implemented</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/african-marine-rules-favour-big-industry-leaving-small-scale-fishers-in-the-lurch-171829">African marine rules favour big industry, leaving small-scale fishers in the lurch</a>
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<p>Part of my expertise lies in maritime and natural resource governance in Africa, so I’ve been following this development. There are reasons to celebrate the <a href="https://news.un.org/en/story/2023/06/1137857">Oceans Treaty</a> for what it represents – an extra mechanism to protect our oceans and their resources. But my main concern – which <a href="https://www.cffacape.org/publications-blog/an-ambitious-high-seas-treaty-must-not-come-at-the-expense-of-coastal-fishing-communities">has also been flagged</a> by others – is that the treaty could drive distant water fleets (fishing outside their own territory) to fishing grounds closer to land. And many of the most lucrative grounds belong to African countries. </p>
<p>The treaty has been described as “<a href="https://www.nature.com/articles/s44183-023-00013-x#:%7E:text=The%20new%20Treaty%20lays%20out,high%20seas%2C%20among%20other%20things">extremely broad</a>” and lacking specifics. Clear regulations must be put in place by the treaty’s implementing agency. It’s not yet clear who that will be. The treaty calls for state parties to allow for the establishment of various committees and working groups, together with a Conference of the Parties to guide implementation. </p>
<p>I argue that clear regulations must ensure that fisheries subsidies to vessels that once relied on the high seas must be cut. Subsidies given to <a href="https://oceana.org/wp-content/uploads/sites/18/OceanaDWF_FinalReport.pdf">distant water vessels</a> can encourage the <a href="https://theconversation.com/eu-targets-fragile-west-african-fish-stocks-despite-protection-laws-125679">overexploitation</a> of vulnerable species.</p>
<h2>Attractive fishing grounds</h2>
<p>Having lost access to fish on the high seas, fleets will need new fishing grounds. African waters are an attractive target for various reasons.</p>
<p>Firstly, they’re <a href="https://thedocs.worldbank.org/en/doc/a0053a27595217fd04745ae65f88e092-0320012022/original/Coastal-and-Marine-Biodiversity-and-Ecosystems.pdf">rich</a> in <a href="https://wwf.panda.org/discover/knowledge_hub/where_we_work/west_africa_marine/">diverse</a> species.</p>
<p>Secondly, these waters are not properly monitored, which means countries can take advantage of them. Illegal, unreported and unregulated fishing already costs Africa <a href="https://www.wto.org/english/news_e/news23_e/fish_12jul23_e.htm">over US$2.3 billion</a> annually. </p>
<p>Thirdly, coastal African states <a href="https://theconversation.com/african-marine-rules-favour-big-industry-leaving-small-scale-fishers-in-the-lurch-171829">appear willing</a> to enter into new <a href="https://chinadialogueocean.net/en/fisheries/opinion-some-fishing-deals-in-west-africa-make-little-economic-sense/">agreements</a> with nations that fish outside their own borders. </p>
<p>This is worrying because it’s going to put Africa’s vulnerable fish stocks at risk. Distant-water vessels are already known to be exploitative. </p>
<h2>Who are these vessels?</h2>
<p>About <a href="https://www.pewtrusts.org/en/research-and-analysis/issue-briefs/2022/03/high-seas-treaty-must-reflect-critical-role-of-fish-in-marine-ecosystems">97% of high-seas fishing</a> is done by vessels flagged to high-income countries – the vast majority (<a href="https://www.pewtrusts.org/en/research-and-analysis/issue-briefs/2022/03/high-seas-treaty-must-reflect-critical-role-of-fish-in-marine-ecosystems">86%</a>) are from China, Taiwan, Japan, South Korea and Spain. </p>
<p>Vessels from some of these countries, such as <a href="https://adf-magazine.com/2023/03/six-west-african-countries-account-for-20-of-worlds-illegally-caught-fish/">China</a>, <a href="https://cimsec.org/looking-past-gulf-of-guinea-piracy-chinese-twins-ghanaian-fishing-and-domain-awareness/">South Korea</a> and <a href="https://www.theeastafrican.co.ke/tea/business/spanish-french-fleets-blacklisted-indian-ocean-illegal-fishing-3844968">Spain</a>, already have fisheries arrangements with countries in Africa. And they’re known to contribute to the <a href="https://qz.com/africa/1807878/eu-subsidies-boost-overfishing-in-west-africa-and-migration#:%7E:text=Countries%20like%20Spain%20in%20particular,artisanal%20fishermen%20in%20West%20Africa">overexploitation</a> of fish on the continent through legal and illegal fishing.</p>
<h2>Harmful subsidies</h2>
<p>These high-sea fishing vessels come from the <a href="https://oceana.org/wp-content/uploads/sites/18/OceanaDWF_FinalReport.pdf">top 10 countries</a> providing fisheries subsidies. </p>
<p>Fisheries subsidies are financial support given by governments to help the private sector, including <a href="https://oceana.org/wp-content/uploads/sites/18/OceanaDWF_FinalReport.pdf">distant-water vessels</a>, to catch more fish. Some of these subsidies have been shown to be <a href="https://theconversation.com/eu-targets-fragile-west-african-fish-stocks-despite-protection-laws-125679">harmful</a>, particularly to vulnerable species. </p>
<p>Harmful subsidies <a href="https://www.pewtrusts.org/en/trust/archive/winter-2023/a-global-deal-to-end-harmful-fisheries-subsidies">encourage</a> overfishing, as the money is spent on capacity-expanding activities such as artificially lowering fuel and vessel construction costs. This allows large vessels to catch more fish than is sustainable by fishing farther out to sea and for longer periods. Many industrial fleets <a href="https://unctad.org/news/too-large-be-missed-how-fleet-size-and-harmful-subsidies-undermine-fish-stocks-sustainability">wouldn’t be profitable</a> without these subsidies.</p>
<p>The treaty doesn’t clearly address subsidies, but they are the subject of the World Trade Organization’s 2022 <a href="https://www.wto.org/english/tratop_e/rulesneg_e/fish_e/fish_e.htm">Fisheries Subsidies Agreement</a>. This, however, has not come into force as two thirds of the signatories have not yet accepted the deal. Under the proposed agreement, signatory countries must commit to stop providing harmful subsidies.</p>
<p>If harmful subsidies aren’t effectively addressed, a ban on fishing on the high seas could end up contributing to increased fishing activities within the jurisdictions of coastal countries. </p>
<h2>What must happen</h2>
<p>Aside from the treaty being effectively implemented, several measures and strategies can be deployed to ensure African countries are protected.</p>
<p>There must be more support from the international community for regional fisheries bodies – such as the Fisheries Committee for the West Central Gulf of Guinea and <a href="http://www.corep-se.org/">Regional Fisheries Commission for the Gulf of Guinea</a> – for countries in west Africa. The regional bodies must be in a better position to guide member states on sustainable fisheries practices, enforce regulations where they exist or update regulations as needed.</p>
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Read more:
<a href="https://theconversation.com/fisheries-subsidies-fuel-ocean-depletion-and-hurt-coastal-communities-142260">Fisheries subsidies fuel ocean depletion and hurt coastal communities</a>
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<p>There must be increased support in monitoring fishing. Partners and non-governmental organisations <a href="https://www.tm-tracking.org/joint-analytical-cell">share data</a> from satellite technology and vessel tracking systems that helps coastal states monitor what goes on in their waters. The international community must provide further support so that coastal states can enforce existing regulations by sharing capacity, technological know-how and assets.</p>
<p>By combining these strategies and fostering international cooperation, it is possible to strike a balance between implementing the treaty and fishing sustainably in Africa’s oceans.</p><img src="https://counter.theconversation.com/content/214422/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ifesinachi Okafor-Yarwood receives funding from the Scottish Funding Council through the University of St Andrews and the PEW Charitable Trust. </span></em></p>A new ocean treaty could redirect the unsustainable fishing practices that were happening on the high seas to coastal African nations.Ifesinachi Okafor-Yarwood, Lecturer, University of St AndrewsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2115802023-10-03T21:37:30Z2023-10-03T21:37:30ZClimate change challenges marine conservation efforts in Atlantic Canada<figure><img src="https://images.theconversation.com/files/551036/original/file-20230928-17-ua1o1p.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4031%2C2751&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The oceans are rapidly warming and Canada's marine protections must be able to adapt quickly to meet these changes.</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/VGRlfwv6nzY">(Brittany Griffin, Unsplash)</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/climate-change-challenges-marine-conservation-efforts-in-atlantic-canada" width="100%" height="400"></iframe>
<p>Extreme ocean changes due to climate change are not an abstract or future scenario. This summer alone, <a href="http://whalemap.ocean.dal.ca/MHW/">23 per cent of the world’s oceans experienced a heat wave</a>, corresponding to an area roughly equivalent to the entire Atlantic Ocean. </p>
<p>Those extreme events, against a backdrop of more gradual global warming, have <a href="https://doi.org/10.1146/annurev-marine-032122-121437">widespread effects on ocean life and their environments</a>. For example, some species might leave their preferred environment in favour of more suitable temperatures, others might adapt locally or go extinct. </p>
<p>While climate change impacts are pervasive, marine protected areas and refuges can <a href="https://doi.org/10.1126/sciadv.aay9969">safeguard species, and improve ecosystem resilience, by minimizing additional human impacts</a>.</p>
<h2>Marine conservation in Canada</h2>
<p>In Canada, there is a surprising <a href="https://doi.org/10.1139/facets-2021-0122">lack of conservation planning and management</a> to address the effects of climate change. <a href="https://doi.org/10.1139/facets-2023-0024">Our recent study showed</a> that most marine protected areas (especially in Atlantic Canada) are located in regions set to undergo rapid, substantial changes, making them unsuitable as marine life sanctuaries.</p>
<p>These results emphasize the need to account for climate change impacts and adaptations in marine conservation planning in Canada and beyond. Ideally, refuges, hotspots and other climate futures should be factored into any planning on Canada’s marine protected area network.</p>
<p><a href="https://www.washingtonpost.com/weather/2023/07/28/ocean-temperature-maps-heat-records/">Parts of the Canadian Atlantic Ocean are already warming at a higher rate than the global average</a>. This is projected to continue throughout the 21st century. </p>
<p>Alarmingly, the waters off of Nova Scotia and Newfoundland — <a href="https://www.dfo-mpo.gc.ca/stats/commercial/land-debarq/sea-maritimes/s2020pv-eng.htm">regions known for lucrative fisheries</a> — are seeing temperature increases <a href="https://www.washingtonpost.com/weather/2023/07/28/ocean-temperature-maps-heat-records/">beyond the most extreme projections for this century</a>. </p>
<p><a href="https://www.dfo-mpo.gc.ca/oceans/conservation/areas-zones/index-eng.html">Many of the existing marine protected areas and marine refuges in these regions </a> were put in place to protect critical habitat and life stages of commercially important fish and invertebrate species. However, these protections may become ineffective as the climate changes.</p>
<h2>Projecting marine climate change</h2>
<p>To effectively address the climate change challenges for marine conservation in Atlantic Canada, <a href="https://doi.org/10.1139/facets-2021-0122">current conservation efforts need to become more adaptive both in their planning and management</a>. <a href="https://doi.org/10.3389/fmars.2021.711085">Most marine protected areas in Canada</a> are not planned or managed with the effects of climate change in mind. </p>
<p>To become more adaptive, we need to know what is happening below the surface and, crucially, <a href="https://doi.org/10.3389/fmars.2021.711085">which areas, habitats and species are most vulnerable</a>. These insights will enable more effective strategies. </p>
<p>The first step in determining which areas and species are most at risk from climate change is to use projections from ecosystem models under different climate change scenarios. This together with assessments of how vulnerable different areas and species are to those changes will allow a much clearer picture. </p>
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Read more:
<a href="https://theconversation.com/canadas-marine-conservation-toolbox-needs-an-overhaul-to-counter-climate-change-177895">Canada's marine conservation toolbox needs an overhaul to counter climate change</a>
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<p>We used a state-of-the-art modelling approach to help us project and understand potential future changes in the Northwest Atlantic Ocean. For this, we combined future projections from nine global marine ecosystem models and two climate models that provide standardized output data. </p>
<p>These data sets give us insights on future changes in, for example, fish biomass, temperature or oxygen availability in the water.</p>
<h2>Developing hotspots</h2>
<p>Based on the results, our research identified both climate change hotspots and refuges. We also investigated whether those hotspots or refuges overlap with existing marine conservation areas. Most areas overlapped with climate change hotspots, none with climate change refuges.</p>
<p>Considering that climate refuges are areas that are likely to experience less rapid ecosystem changes, protecting those can minimize additional impacts — such as the effects of intensive commercial fishing or oil and gas development — <a href="https://doi.org/10.1016/j.scitotenv.2020.142564">to support overall resilience to climate change</a>.</p>
<p>Simply put, a system or species that is less stressed and more healthy is <a href="https://doi.org/10.3389/fmars.2020.00523/full">better equipped to face the impacts of climate change</a>.</p>
<p>In adapting marine conservation planning to climate change, protecting climate change refuges may allow more time for particular species and ecosystems to adapt, potentially slowing rates of local extinction. Such refuges could also act as stepping-stones for species as they move to more favourable habitats due to rapid ecosystem changes. </p>
<p>On the other hand, hotspots of climate change impacts that experience rapid, substantial ecosystem changes may foster adaptation and evolution in some species, so they are better equipped to respond to a changing future. </p>
<p>Such a network would aim to span a diverse range of potential future climate conditions and ecosystem states, essentially protecting a wide range of marine biodiversity.</p>
<p>Together with an adaptive marine conservation approach — that includes flexible and dynamic planning, monitoring and management — Canada would be better equipped to protect its ocean’s biodiversity and resources.</p>
<h2>Climate futures are present</h2>
<p>The reality is that climate change is not just a future scenario but is already altering Canada’s ocean. Today, <a href="https://www.washingtonpost.com/weather/2023/07/28/ocean-temperature-maps-heat-records/">the ocean has never been warmer</a>, with some regions breaking temperature records, stressing the need to start today to adapt ocean governance and marine conservation to climate change. </p>
<p>Ultimately, by re-calibrating the marine conservation approach that builds in climate change impacts, Canada can protect existing biodiversity and the adaptive capacity of marine ecosystems for generations to come.</p><img src="https://counter.theconversation.com/content/211580/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>For this study, Andrea Bryndum-Buchholz received funding from the Ocean Frontier Institute.</span></em></p>As oceans warm, Canada’s marine protections system looks woefully inadequate. New monitoring systems and flexible governance can help Canada protect the areas most likely to have the greatest impact.Andrea Bryndum-Buchholz, Postdoctoral Researcher in Marine Ecology and Climate-Impact Sciences, Memorial University of NewfoundlandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2104672023-08-31T20:00:16Z2023-08-31T20:00:16ZFriday essay: traps, rites and kurrajong twine – the incredible ingenuity of Indigenous fishing knowledge<p>Standing on a ferry chugging across Sydney Harbour, it’s still possible to imagine the city as it was in 1788 – before the span of the bridge, before the marinas and yachts, before buildings were planted onto that sloping, rocky landscape. Pockets of bush still reach down towards the water, where gums and angophoras curl around sandstone coves carved out by the sea water.</p>
<p>Ferries stop at Mosman, Manly and Milsons Point, where fishers share the wharf with boats and commuters. They perch on folding chairs next to white buckets of bait, or they plonk down on the wooden beams, rod in hand, their legs dangling over the edge as they sit.</p>
<p>Yet these places were also occupied, named and fished, long before “Sydney” appeared on any charts. And it’s at one of these harbour places, at Kay-ye-my, or perhaps Goram Bullagong (present-day Manly Cove and Mosman Bay), that our first story of Indigenous fishing is set. (After all, Kiarabilli or Kiarabily – the site of present-day Milsons Point and Kirribilli – is believed to translate into English as “good fishing spot”.)</p>
<p><em>Malgun</em> – the amputation of the joint of a young girl’s left little finger – is one of many Aboriginal fishing rites that took place and was practised along much of the east coast of what’s now known as Australia. Across the continent, diverse and adaptable fishing practices, recipes and rituals were a cornerstone of Indigenous life at the time of first contact – and many remain so to this day.</p>
<p>Like <em>keeparra</em> (the knocking out of teeth) and scarification, <em><a href="https://dictionaryofsydney.org/entry/daringa">malgun</a></em> is a custom rich with significance, an offering to the spirits. In this case, the little girl would be forever linked with the fish she had literally fed. And as these girls grew into women, that connection to the underwater world was thought to offer good fortune and prowess with a fishing line. </p>
<p>It’s thought that <em>malgun</em> was also about the practicalities of fishing, since a shorter left pinky could apparently wind a hand line in more nimbly. The practice was observed among Aboriginal communities along the eastern seaboard of Australia (and featured around the country in various forms). But its meaning was frequently misunderstood in early colonial encounters and is still open for speculation.</p>
<p>To make the line, or <em>currejun/garradjun</em>, Gadigal fisherwomen used the bark or the tender fibres of young kurrajong trees, which they soaked and pounded or sometimes chewed, scraping off the outer layers with a shell. The pliable strands were then worked into <a href="https://aiatsis.gov.au/publication/35662">fine strong thread</a>. The women cast out their handlines and quickly drew them back in on the strike, hand over hand, before the fish could shake off the hook.</p>
<p>I like to picture the women sitting on a beach or around a fire as they made their string, humming, singing and chatting. They rolled the fibres along their thighs methodically, slowly turning them into lengths of delicate but durable fishing twine. Even the name of this beautiful and distinctive tree provides a valuable historical link to a time when fishing dominated the physical, social and cultural life of coastal Aboriginal peoples. What they sang and nattered about, while swatting mosquitoes and shooing away curious children, we can only guess.</p>
<p>At the end of these lines, elegant fishhooks, or <em>burra</em>, made from carved abalone or turban shells were dropped over the side of their canoes, or nowies. In other parts of Australia, hooks made from a piece of tapered hardwood, bird talon or
bone have also been found. These “nowies were nothing more than a large piece of bark tied up at both ends with vines”, described the British officer Watkin Tench in his <a href="https://www.gutenberg.org/files/3534/3534-h/3534-h.htm">account of early Sydney</a>.</p>
<p>Despite the nowies’ apparent flimsiness, the fisherwomen were master skippers. They paddled across the bays and out through the Heads, waves slapping at the sides of their precarious little vessels. That mobility was essential for Aboriginal communities around the harbour – such as the Gadigal, Gayamaygal, Wangal, and Darramurragal – who needed to chase shoals and find new grounds if the fishing was quiet at particular times of the year. Small fires were lit in the nowie on a platform of clay and weed before the craft was launched into the water from a snug harbour cove. </p>
<p>Then the fisherwoman perched inside and paddled to a favourite spot or two, often with a baby cradled in her lap and an infant on her shoulders or crouched beside her. Out on the water, she chewed crustaceans and shellfish, spitting some out into the water before jigging her pearlescent hook up and down like a lure. </p>
<p>This sort of berleying was practised all around Australia in the hope of generating a bit more action – thousands of years before punctured tins of cheap cat food dropped off the back of a tinnie to attract fish became the norm. When the fisherwoman threw the line overboard, she waited for that strike and tug from a whiting, dory or snapper, which would be quickly hauled aboard and charred on the waiting fire. And she sang as she fished, as <a href="https://www.allenandunwin.com/browse/book/Grace-Karskens-Colony-9781742373645">Grace Karskens</a> describes in her wonderful book on colonial Sydney, her voice carrying across the bays and inlets and down through the water to the fish below. </p>
<p>Those fishing songs also captured the attention of colonists, such as the colonial judge advocate <a href="https://www.gutenberg.org/files/12565/12565-h/12565-h.htm">David Collins</a>, who described seeing Carangarang and Kurúbarabúla (the sister and wife of Bennelong, respectively) return from a canoe trip “to procure fish” and they “were keeping time with their paddles, responsive to the words of a song, in which they joined with much good humour and harmony”.</p>
<p>Some, like the French explorer Louis de Freycinet, were so transfixed by the songs they overheard bouncing over the water they attempted to write them down in <a href="https://www.sydney.edu.au/paradisec/australharmony/checklist-indigenous-music-1.php#005-2">musical notation</a>.</p>
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Read more:
<a href="https://theconversation.com/friday-essay-on-listening-to-new-national-storytellers-61291">Friday essay: on listening to new national storytellers</a>
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<h2>Fishing archives</h2>
<p>While women were the anointed shellfish gatherers in Aboriginal and Torres Strait Islander communities, as well as line fishers in the areas where that was practised, spearfishing was largely the preserve of men – and this continues to be the case today. Hunters stalked the water’s edge or stood in a canoe, looking for the telltale shadow of a dusky flathead or the flash of silver from a darting bream.</p>
<p>When the water was calm and clear enough, Aboriginal men around Warrane-Sydney Harbour and Kamay-Botany Bay were frequently seen lying across their nowies, faces fully submerged, peering through the cool blue with a spear at the ready. “This they do with such certainty, as rarely to miss their aim,” wrote the painter and engraver John Heaviside Clark in 1813. </p>
<p>At night, Aboriginal fishermen took the canoes out onto the water with their flaming hand torches held aloft. The <a href="https://catalogue.nla.gov.au/catalog/114667">light lured the fish to the boat’s side</a>, where they were speared by a barbed prong whittled out of bone, shell or hardwood. In the muddy mangroves of northern Australia, fires were sometimes lit on creek banks to attract barramundi, which swam towards the light and suffered the same fate. </p>
<p>Beautiful images from the early days of the colony demonstrate the country we can still see traces of today: folds in the landscape as it stretches out across the horizon, the bush reaching right down to the water’s edge, protected sandy coves perfect for camping and fishing. They also show us the centrality of fishing to
First Nations communities. These sources depict how Aboriginal people fished and what they caught, like a juicy snapper flailing on the end of a spear, or a fisherwoman managing both an infant and a fishing line in her nowie. The skill of these fishers and the abundance of fish are lasting impressions from these visual records.</p>
<p>While early colonial sketches and paintings give wonderful snapshots of Aboriginal fishers, they do so from a European perspective. Written accounts are similarly revealing, and we can be grateful for the faithful record of fishing practices and
winning catches they’ve produced. But we can’t forget that these people viewed First Nations societies through a distinctly colonial lens.</p>
<p>The early colonial view of Australia was mostly curious and enlightened, and colonists were often captivated by the extraordinary skills of Aboriginal fishers, as well as their depth of knowledge about their Country. Yet they were also
people of their time, who saw the British expansion in Australia as inevitable, and viewed Country as a resource awaiting exploitation.</p>
<p>Sometimes, vital Indigenous perspectives creep in. Scars on the mighty trunks of river red gums, or canoe trees, along the banks and flood plains of the Murray River reveal an Aboriginal presence long before any European record. Enormous
engravings of whales, fish and sharks etched into sandstone platforms around Sydney and into the rugged iron ore of Murujuga-Burrup Peninsula in Western Australia have a provenance thousands of years older than any colonial etching or
journal entry. Elaborate fish traps across the continent and the Torres Strait demonstrate intricate knowledge of seasonal and tidal fish aggregations.</p>
<p>Paintings in smoke-stained caves across northern Australia show equally distinctive Aboriginal readings of fishy feats and feasts. And the remnants of literally millions of seafood meals can be seen in middens around the continent
that cascade through dirt, sand and mud at the water’s edge. </p>
<p>These Indigenous archives give us a glimpse into fishing before European colonisation. They also reveal the ingenuity of pre-industrial First Nations communities, long before fish finders, weather apps and soft plastics.</p>
<p>Remnants of vast, curving fish traps, or Ngunnhu, made from river stones still lie near Brewarrina in central New South Wales. (There were even more Ngunnhu once, until they were pushed aside to make way for paddle-steamers taking the wool clip down to Adelaide in the late 19th century.)</p>
<p>In the early spring or during a large flow of fresh water after heavy rains, enormous numbers of fish would travel upriver, swelling the eddies and currents with a mass of writhing tails and fins. Aboriginal fishers – men and women from the Ngemba, Wonkamurra, Wailwan and Gomeroi nations – kept watch from grassy embankments above the river and, as soon as enough fish had entered the labyrinth of traps, they rolled large rocks across the openings, ensnaring them for a <a href="https://nla.gov.au/nla.obj-756525252/view?partId=nla.obj-756525911#page/n0/mode/1up">seasonal fish feast</a>. </p>
<p>These traps and weirs were also an early form of fisheries management – well before government regulations and research organisations – and remnants can be seen right across central and western New South Wales. Juvenile fish were carried in curved wooden coolamons and released behind the barriers on the smaller tributaries as a way of boosting stocks and ensuring fish for seasons to come.</p>
<p>The <a href="https://www.budjbim.com.au/">Budj Bim</a> eel traps at Lake Condah in southwest
Victoria were designed, built and maintained by the Gunditjmara people, who operated the series of channels, locks and weirs. Built at least 6,600 years ago, the traps have been redeveloped several times over several centuries, and they
demonstrate an ecologically sustainable management of this freshwater eel fishery that was adapted and lasted for thousands of years. What’s more, they can still be seen today.</p>
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Read more:
<a href="https://theconversation.com/the-detective-work-behind-the-budj-bim-eel-traps-world-heritage-bid-71800">The detective work behind the Budj Bim eel traps World Heritage bid</a>
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<p>Other traps were less permanent, but just as effective. When particular waterholes were low in the Baaka-Barwon–Darling river system in New South Wales, Barkindji people living along the river used wooden stakes, logs and sometimes stones to build shallow pens that trapped fish, yabbies and eels for easy pickings.</p>
<p>The ill-fated explorer William John Wills described a similar “arrangement for catching fish” somewhere north of Birdsville around the Georgina River, where he camped with Robert O’Hara Burke and the rest of their party in January 1861. The
trap consisted of “a small oval mud paddock about 12 feet by 8 feet, the sides of which were about nine inches above the bottom of the hole,” he wrote. The “top of the fence” was “covered with long grass, so arranged that the ends of the blades overhung scantily by several inches the sides of the hole.”</p>
<p>Periods of drought and seasonal dry weather could change rivers from torrential, turgid flows to the most meagre trickle – a chain of muddy holes through the landscape. Across northern Australia, seasons of wet and dry charged the landscape with weather cycles that pushed water across the floodplains of the northern savanna in great sheets, and then inevitably dried them out again.</p>
<p>But even low water could mean good fishing, since the fish would be forced to aggregate in particular waterholes, where they could be readily trapped and caught. While the grass might be parched and brittle up on the banks, the water
below was teeming with life; that was the time when Aboriginal people walked along the creek bottom, muddying the water and forcing the fish to rise and take in air where they were easily speared, clubbed or netted. </p>
<p>In the <a href="https://books.google.com.au/books/about/Gunanurang.html?id=I2CaNAAACAAJ&redir_esc=y">Kimberley</a>, when the dry season came and the floodwaters finally receded, rolls of spinifex were used to entangle fish that had been trapped in the
remaining waterholes. </p>
<h2>Fishing objects and artefacts</h2>
<p>Artefacts such as spears, hooks and nets also help reconstruct some of the changing ways and means of Indigenous fishing that predate European colonisation and continue to be used and modified long after it. These relics are as beautiful
as they were effective. </p>
<p>Kangaroo tail tendon was used to bind fishhooks in northern Australia. The prongs of spears (fish gigs or fizgigs) were hardened and polished and then attached to the long shaft using pieces of thread daubed with resin.</p>
<p>Meanwhile, nets made from lengths of finely twisted twine were so carefully knotted together that when <a href="https://gutenberg.net.au/ebooks/e00101.html">Governor Phillip</a> showed them to the white women in the colony, the elegant loops reminded them of English lace. Those nets came in all shapes and sizes and were highly prized possessions. To strengthen the nets’ fishing powers, Aboriginal people sang to them: their music and words, literally singing in the fish, were like charms for the Dreaming that cascaded through the weave. </p>
<p>In the area of what’s now known as Sydney, coastal tribes used small hoop nets to pick up lobsters, which hid in underwater crevasses on the edge of the harbour and along the beachside cliffs. Catch-and-cast nets trapped small numbers of fish in creeks and waterholes near the coast and could also be used to carry a feed of fish as families walked back to their camps along the well-worn walking tracks.</p>
<p>Further inland, Aboriginal people made large woven river nets, which could be held by hand or propped up along the bank. Once fixed in place, groups of people waded through the murky water, loudly beating the surface and driving the startled
fish into the mesh. </p>
<p>The nets were usually about four metres long and one metre deep – sizeable enough, considering every strand was gathered, spun and woven by hand. But one extraordinary account from the explorer Charles Sturt described how his exploration party on the Wambuul-Macquarie River in western New South Wales discovered a fishing net some 90 metres long in a Wiradjuri village they came across.</p>
<p>Other fishing methods have been recorded and described in oral histories, or they’ve been passed down and are practised still. These practices are a form of embodied or “living archives”, which is how we know about them today. Stories
of women diving deep underwater for shellfish, walking out across the rocks at low tide pulling off abalone, or wading through billabongs to pick up turtles, are common in accounts from the time and these practices are still maintained by many
Indigenous communities around Australia and the Torres Strait Islands. </p>
<p>Given such longstanding fishing connections, “sea rights” have been increasingly recognised by governments in legislating fisheries management. Back on the beach or riverbank, a fire is inevitably on the go in anticipation of a <a href="https://www.environment.nsw.gov.au/resources/cultureheritage/20120945CoastalHistory.pdf">fresh catch</a>. The fish is usually chucked on whole and eaten.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-moon-plays-an-important-role-in-indigenous-culture-and-helped-win-a-battle-over-sea-rights-119081">The Moon plays an important role in Indigenous culture and helped win a battle over sea rights</a>
</strong>
</em>
</p>
<hr>
<p>Some of the environmental knowledge used by Traditional Owners seems astonishing in today’s context of mass-produced fishing lures and frozen bait from the local servo. <a href="https://catalogue.nla.gov.au/catalog/114667">One account from northern Australia</a> described a particularly large Golden Orb spider carefully killed to preserve its abdomen, which was then gently squeezed to milk its adhesive goo. Small fish, attracted to the carcass, would then get stuck to the dead spider before being delicately lifted ashore by nimble
hands. </p>
<p>Fish poisoning, using various berries, roots, leaves and stems, was also common throughout Australia. In the Kimberley around the Goonoonoorrang-Ord River in
Western Australia, Traditional Owners such as the Miriuwung, Kuluwaring, Gajerrabeng used crushed leaves from the freshwater mangrove (malawarn) to poison their prey, sweeping branches through the water until stunned fish started floating belly up. </p>
<p>Along the east coast it was wattle leaves that did the damage. The sunny, fragrant puffballs of two common acacias (<em>Acacia implexa</em> and <em>Acacia longifolia</em>) belie their potency as a fish poison. Once absorbed through the gills, antigens from the bruised leaves were quickly catastrophic for fish in little waterholes and
billabongs. <a href="https://books.google.com.au/books?id=QvwrAAAAYAAJ&printsec=frontcover#v=onepage&q&f=false">There are even accounts</a> of eels gliding out of the water and into the bush along the Clarence River in northern New South Wales (known as Boorimbah to the Bundjalung and Ngunitiji to the Yaygir) in an attempt to escape poisoning from Aboriginal fishers. </p>
<p>Although these poisoning methods apparently had no effect on the edibility of the fish, the trick was to carefully manage the immersion of these toxic branches in the water – giving just enough poison to stun the fish , but not enough to knock out the whole waterhole. </p>
<p>That intimate knowledge and understanding of Country and its seasons wasn’t readily apparent to the early colonists. Watkin Tench was so perplexed by the unpredictability of fishing in Australia that he complained about spending all night out on Sydney Harbour for little result. The “universal voice of all professed fishermen”, he lamented in the 1790s in A Complete Account of the Settlement at Port Jackson, was that they had “never fished in a country where success was so precarious and uncertain”.</p>
<p>It was knowledge that came slowly to the colonists, over several generations. William Scott, the New South Wales colonial astronomer from 1856 to 1862, observed how the Worimi people were able to anticipate fishing seasons around Port Stephens on the New South Wales Mid North Coast. “By some unerring instinct the blacks knew within a day when the first of the great shoals [of sea mullet] would appear through the heads,” he explained.</p>
<p>For the Yolŋu in Arnhem Land, flowering of stringybark trees coincides with the shrinking of waterholes, where fish can be more readily netted and speared, or poisoned. And when the <a href="https://aiatsis.library.link/portal/Dharawal--seasons-and-climatic-cycles-compiled/8ypS2t3XXEc/">Dharawal people</a> of the Kamay and Shoalhaven region in New South Wales see the golden wattle flowers of the <em>Kai’arrewan (Acacia binervia)</em>, they know that the fish will be running in the rivers and prawns will be schooling in estuarine shallows. </p>
<p>In Queensland the movement and population of particular fish species have their own corresponding sign on land. The extent of the annual sea-mullet run in the cool winter months can be predicted by the numbers of rainbow lorikeets in late
autumn; if magpies are scarce in winter, numbers of luderick will also be low; and when the bush is ablaze with the fragrant sunny blooms of coastal wattle in early spring, surging schools of tailor can be expected just offshore. Although climate
change may shift these fishing markers in the natural world.</p>
<p>This knowledge was acquired by Australia’s Indigenous peoples through generations of observation and practice. What’s more, that deep understanding was as much about the spirit world as the natural. Neither can be properly comprehended
without reference to the other – although our own contemporary insights are often sketchy, since the sporadic observations of colonists are frequently the only available historical sources we have of Indigenous fishing practices, which had been developed over millennia.</p>
<p>Practical understanding was intimately entwined with spiritual readings of the land. First Nations Dreamings are systems of cultural values and observations: they created the world and are reflected in day-to-day observations of that life. These “<a href="https://www.researchgate.net/publication/233438480_Saltwater_People_spiritscapes_maritime_rituals_and_the_archaeology_of_Australian_indigenous_seascapes">spiritscapes</a>”, as the archaeologist Ian McNiven has called them, infused Country with cosmology. The natural and spirit worlds were one and the same. Country wasn’t inanimate – it
could feel and do. And for many Aboriginal people to this day, that knowledge remains a shaping, dynamic belief system.</p>
<p>There are accounts on the South Australian coastline of Aboriginal people ritually singing in dolphins or sharks to herd fish into man-made or natural enclosures on the Eyre and Yorke Peninsulas. In <a href="https://catalogue.nla.gov.au/catalog/1756993">Twofold Bay</a>, on Yuin Country in southern New South Wales, dolphins were similarly used to herd fish, and a totemic bond between killer whales and Aboriginal people was also observed and documented. </p>
<p>Why did Aboriginal communities around Sydney avoid eating sharks and stingrays? The water was full of them, but they were only ever eaten during times of food scarcity. William Bradley, a first lieutenant on the First Fleet, observed Aboriginal people catching “jew fish, snapper, mullet, mackerel, whiting, dory, rock cod and leatherjacket” throughout the summer, but they didn’t keep the sharks or rays. “There are great numbers of the sting ray and shark, both of which I have seen the natives throw away when given to them and often refuse them when offered”, he noted.</p>
<p>In Lutruwita-Tasmania, <a href="https://www.jstor.org/stable/24046726">archaeological excavations of middens</a> suggest Palawa people mysteriously avoided eating finfish altogether for the 3000 years prior to colonisation, hunting mammals and scavenging shellfish instead. Was it spiritual? A response to some sort of poisoning event? Or an economic decision to harvest easier resources (such as seals and abalone)? Did the community lose their knowledge of fishing, as some have argued? Or did they perhaps dispose of the bones somewhere else? No one really knows. </p>
<p>Some forms of Indigenous fishing inevitably became lost as Traditional Owners were dispossessed and disenfranchised of their lands and fisheries following the expansion of the colonial frontier post-1788. Many Indigenous practices were eventually superseded by new technologies. Other Indigenous fishers became active in the establishment of the commercial fishing industry in Australia, maintaining strong links to traditional knowledges, as well as adapting to modern fishing approaches and technologies.</p>
<p>Indigenous peoples have played and continue to play a prominent role in the history of Australian fishing. </p>
<p>Despite the ruptures of colonisation, the cultural and social cleavages wrought by disease, as well as frontier violence and dispossession, they remain a visible and vital part of Australian fishing culture as commercial and recreational fishers, industry partners and Traditional Owners of the vast natural resource that is Australia’s fisheries.</p>
<hr>
<p><em>This is an edited extract from <a href="https://www.penguin.com.au/books/the-catch-9781761342202">The Catch: Australia’s Love Affair with Fishing</a> by Anna Clark (Penguin).</em></p><img src="https://counter.theconversation.com/content/210467/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anna Clark has received funding from the Australian Research Council and is a member of the Recreational Fishing NSW Advisory Council. </span></em></p>Across the continent, diverse, adaptable fishing practices, recipes and rituals were a cornerstone of Indigenous life at the time of first contact – and many remain so to this day.Anna Clark, Professor in Public History, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2072842023-08-28T12:03:27Z2023-08-28T12:03:27ZWhat social change movements can learn from fly fishing: The value of a care-focused message<figure><img src="https://images.theconversation.com/files/544486/original/file-20230824-17-xz9a9n.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2811%2C1863&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fly-fishing in Alaska's Tongass National Forest.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/fB1dRF">Joseph/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Summer and fall are prime times for getting outdoors across the U.S. According to an annual survey produced by the outdoor industry, 55% of Americans age 6 and up participated in <a href="https://outdoorindustry.org/resource/2023-outdoor-participation-trends-report/">some kind of outdoor recreation</a> in 2022, and that number is on the rise. </p>
<p>However, the activities they choose are shifting. Over the past century, participation has declined in some activities, <a href="https://theconversation.com/fewer-americans-are-hunting-and-that-raises-hard-questions-about-funding-conservation-through-gun-sales-176220">such as hunting</a>, and increased in others, <a href="https://www.nationalgeographic.com/travel/article/could-a-boom-in-us-birding-help-fund-conservation">like bird-watching</a>. </p>
<p>These shifts reflect many factors, including demographic trends and urbanization. But outdoor activities also have their own cultures, which can powerfully affect how participants think about nature. </p>
<p>As scholars who think about <a href="https://scholar.google.com/citations?user=u6FOkIQAAAAJ&hl=en">organizational theory</a>, <a href="https://scholar.google.com/citations?user=F1RxMTcAAAAJ&hl=en">management</a> and <a href="https://scholar.google.com/citations?user=hkKa8JcAAAAJ&hl=en">entrepreneurship</a>, we are interested in understanding effective ways to promote social change. In a recent study, we analyzed the work of the nonprofit group <a href="https://www.tu.org/">Trout Unlimited</a>, which centers on protecting rivers and streams across the U.S. that harbor wild and native trout and salmon. </p>
<p>We found that since its founding in 1959, Trout Unlimited has pursued a unique type of social change. Historically, people fished to obtain food – but Trout Unlimited has reframed the sport as <a href="https://doi.org/10.1177/01708406231159490">a vehicle for environmental conservation</a>. It did this by gradually shifting members from catch and keep practices to catch and release, with fish carefully returned to the water. In our view, this strategy offers a powerful example of energizing social change through care, rather than disruptive strategies that emphasize power, anger and fearmongering.</p>
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<figcaption><span class="caption">John McMillan, science director for Trout Unlimited’s Wild Steelhead Initiative, walks through the proper technique to catch and release a type of coastal rainbow trout called steelhead.</span></figcaption>
</figure>
<h2>A sport that inspires devotion</h2>
<p>Fishing is very popular in the U.S.: As of 2016, <a href="https://www.census.gov/content/dam/Census/library/publications/2018/demo/fhw16-nat.pdf">more then 35 million Americans fished</a>, mainly in fresh water. Trout Unlimited was <a href="https://www.tu.org/about/#:%7E:text=Founded%20in%20Michigan%20in%201959,coldwater%20fisheries%20and%20their%20watersheds.">founded in 1959</a> on the banks of Michigan’s Au Sable River with the aim of building a strong conservation ethic among anglers. Today, the group has more than 300,000 members spanning hundreds of local chapters across the U.S. </p>
<p>Many Trout Unlimited members prefer fly fishing, a technique that uses a rod, reel, specialized weighted fishing line and artificial flies designed to mimic trout’s natural food sources. Trout generally thrive in beautiful, fast-flowing, cold-water streams and rivers; to catch them, fly fishers repeatedly cast a line so that their lure moves like a flying insect landing and floating on the water. It’s a sport that combines deep knowledge of a specific location with time-honored techniques.</p>
<p>In the 1653 classic “<a href="https://www.gutenberg.org/ebooks/683">The Compleat Angler</a>,” English writer Izaak Walton called fly fishing “an art worthy the knowledge and practice of a wise man.” Norman Maclean’s 1976 book “<a href="https://press.uchicago.edu/ucp/books/book/chicago/R/bo3643831.html">A River Runs Through It</a>,” which recounts the author’s childhood experiences fishing Montana’s Big Blackfoot River, declares, “In our family, there was no clear line between religion and fly fishing.” Changing the practices of devoted anglers is no small feat. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CwRq_pAt9je/?utm_source=ig_web_copy_link\u0026igshid=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Fly-fishing and stewardship</h2>
<p>The first stage of change that Trout Unlimited pursued in its interactions with members was what we call mending – fixing aspects of a practice that are seen as problematic or damaging. For Trout Unlimited, that meant subtly removing harvesting practice from images of fly fishing, while simultaneously reinforcing anglers’ deep connections to rivers. </p>
<p>This reframing began in the late 1960s and continues today, as we learned by analyzing cover images and editorials from “Trout,” the organization’s member magazine, and interviewing staffers at Trout Unlimited and others throughout the fly fishing industry. Editors of “Trout” scrubbed away images of harvesting gear, such as <a href="https://www.montanaoutdoor.com/2020/03/creels/">creels</a>, <a href="https://www.youtube.com/watch?v=hrp-r1iavHY">stringers</a> and spears. Instead, they featured photos of trout being safely released and of caught fish remaining underwater in their environment. </p>
<p>These changes did not directly speak to or challenge anglers’ practices. Instead, they worked more subtly. “Trout” editors also began to describe old harvesting artifacts like creels as “something of a curio” and “relics of the past.” </p>
<p>In another editorial shift, the magazine increasingly featured images of vast river landscapes rather than close-up photos of people fishing. This approach elevated the experience of being in nature above that of catching fish. </p>
<p>Editors included poetry and sermonettes in the magazine that modeled normative values of conservation and catch and release practices. Here’s one example: </p>
<blockquote>
<p><em>Carefully I reach out, and lift him in my net,</em></p>
<p><em>But I make sure not to touch him, until my hands are wet.</em></p>
<p><em>For not doing so would damage him, and that would not be right,</em></p>
<p><em>For this indeed I owe him, for such a noble fight.</em></p>
<p><em>As gently as I can, I remove the hook and set him free …</em></p>
</blockquote>
<p>Using words and images, the magazine sought to trigger positive emotions and a sense of deep connection and love for trout. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CSouKfBB_IY/?utm_source=ig_web_copy_link\u0026igshid=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Caring for fishing grounds</h2>
<p>As Trout Unlimited built momentum in the 1960s and ’70s, the organization made river and stream restoration a major priority. This period marked the birth of the modern environmental movement. Americans were recognizing that industrial development was harming precious natural resources, including fishing grounds. </p>
<p>Logging had <a href="https://www.nwcouncil.org/reports/columbia-river-history/logging/">ravaged wetlands and stream banks</a> along river corridors. Dam construction, particularly in Western states, was <a href="https://theconversation.com/removing-dams-from-the-klamath-river-is-a-step-toward-justice-for-native-americans-in-northern-california-196472">blocking fish passage</a>, preventing trout and salmon from swimming upstream to their spawning grounds. Acid drainage from mining operations was <a href="https://www.tu.org/conservation/conservation-areas/watershed-restoration/abandoned-mine-reclamation/">contaminating waterways</a>. And recreational and commercial fishers were over-harvesting many important species.</p>
<p>Trout Unlimited chapters organized events that ranged from local river cleanups to advocating for federal Wild and Scenic designation for free-flowing rivers and streams. This status <a href="https://www.fs.usda.gov/managing-land/wild-scenic-rivers#">protects them from overuse and in-stream development</a>, such as dams and irrigation diversions.</p>
<p>Members also campaigned for dam removal to open up fish spawning habitat and for creating “<a href="https://riverreporter.com/stories/special-trout-fishing-regulations,43375">no-kill” zones</a> along stretches of rivers, where catch and release was required. Trout Unlimited framed these efforts as supporting fly fishing through positive change. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1669845059661881344"}"></div></p>
<h2>An inclusive message</h2>
<p>Today, Trout Unlimited <a href="https://www.tu.org/conservation/">centers conservation in its mission</a> of protecting, reconnecting, restoring and sustaining coldwater fisheries. We see the organization as an important model in a world driven by social media algorithms that <a href="https://theconversation.com/hate-cancel-culture-blame-algorithms-129402">amplify negative emotions</a>. In our view, driving change through actions that represent love and care, rather than <a href="https://doi.org/10.1080/14693062.2022.2143315">anger and shame</a>, could engage more people in tackling major social challenges.</p>
<p>This approach does have limitations. It is useful when a practice can be altered to be more sustainable, as was the case with catch and release. However, as recent research shows, <a href="https://therevelator.org/recreational-fishing-environmental-impact/">recreational fishing still has major environmental impacts</a>, especially on marine species. And sometimes social change requires ending widespread practices altogether. Nonetheless, the key takeaway for us from Trout Unlimited’s work is that social change doesn’t have to vilify in order to succeed.</p><img src="https://counter.theconversation.com/content/207284/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Founded in 1959, the membership group Trout Unlimited has changed the culture of fly-fishing and mobilized members to support conservation. Could its approach work for other social problems?Brett Crawford, Associate Professor of Management, Grand Valley State University Erica Coslor, Senior Lecturer in Management, The University of MelbourneMadeline Toubiana, Associate Professor of Entrepreneurship and Organization, L’Université d’Ottawa/University of OttawaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2074722023-07-25T12:25:16Z2023-07-25T12:25:16ZIn search of the world’s largest freshwater fish – the wonderfully weird giants lurking in Earth’s rivers<figure><img src="https://images.theconversation.com/files/536146/original/file-20230706-27-zfk4cs.jpg?ixlib=rb-1.1.0&rect=357%2C393%2C3941%2C2417&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Alligator gar can grow to gargantuan sizes.</span> <span class="attribution"><span class="source">Zeb Hogan</span></span></figcaption></figure><p>Rivers have been the lifeblood of human civilization throughout history, and yet we know surprisingly little about what lives in many of them – including the giant creatures that prowl their depths.</p>
<p>While we know the biggest animal in the ocean is the blue whale and the largest marine fish is the whale shark, the identity of the world’s largest freshwater fish species long remained a mystery.</p>
<p>Until 2022, that is, when fishers in Cambodia <a href="https://www.bbc.com/news/world-asia-61862169">caught a giant freshwater stingray</a> in the remote reaches of the Mekong River. </p>
<p>Weighing an astounding 661 pounds, the stingray surpassed by 15 pounds a giant catfish caught in Thailand in 2005 that had previously been considered the unofficial record holder.</p>
<p>The discovery marked a milestone in fish biologist Zeb Hogan’s more than two-decade quest to study and protect giant freshwater fish. As a group, these megafish are <a href="https://www.worldwildlife.org/stories/one-third-of-freshwater-fish-face-extinction-and-other-freshwater-fish-facts">among the most endangered</a> animals on the planet.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/FprTA4lOMOk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The world’s largest freshwater fish confirmed so far is a stingray caught in the Mekong River.</span></figcaption>
</figure>
<p>Before releasing the female ray back into the river, Hogan’s research team put an acoustic tracker on her. She has been sending back clues about stingrays’ elusive behavior ever since.</p>
<h2>Colossal catfish and gargantuan gars</h2>
<p>In a new book, “<a href="https://www.amazon.com/Chasing-Giants-Search-Largest-Freshwater/dp/1647790573">Chasing Giants:</a> In Search of the World’s Largest Freshwater Fish,” Hogan and I tell the troubling story of the 30 or so fish species that live exclusively in rivers and lakes and can grow to <a href="https://www.nationalgeographic.com/animals/article/wild-explorers-zeb-hogan-monster-fish">more than 200 pounds</a> or at least 6 feet (1.8 meters) long.</p>
<p>Found on all continents except Antarctica, they are a wonderfully weird bunch of creatures, from colossal catfish and carp to gargantuan gars. </p>
<figure class="align-center ">
<img alt="A man in the water next to a giant catfish. The fish's giant eye appears to be looking toward the camera. The fish's head is far larger than the man's." src="https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=427&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=427&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=427&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=536&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=536&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536168/original/file-20230706-24-puzybz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=536&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Mekong’s giant catfish can grow to lengths and weights much larger than those of the humans catching them.</span>
<span class="attribution"><span class="source">Zeb Hogan</span></span>
</figcaption>
</figure>
<p>But freshwater vertebrate populations have declined over the past five decades at <a href="https://wwf.panda.org/discover/our_focus/freshwater_practice/freshwater_biodiversity_222/">twice the rate</a> experienced by species within terrestrial or marine ecosystems. Megafish numbers in particular fell by a shocking 94%, according to <a href="https://www.doi.org/10.1111/gcb.14753">one study</a> of more than 200 large freshwater species.</p>
<p>One of the largest species, the Chinese paddlefish, is <a href="https://doi.org/10.1016/j.scitotenv.2019.136242">believed to have gone extinct</a> sometime in the 2000s. “This is a fish that had been on Earth for more than 100 million years before disappearing in a flash,” says Hogan, who used to host National Geographic’s “<a href="https://www.natgeotv.com/za/shows/natgeo/monster-fish">Monster Fish</a>” television show and now leads a University of Nevada, Reno, research project I am involved with called <a href="https://www.usaid.gov/cambodia/fact-sheet/wonders-mekong">Wonders of the Mekong</a>, supported by the U.S. Agency for International Development.</p>
<figure class="align-center ">
<img alt="Several preserved fish in a museum display, with the top one a long fish with a long snout." src="https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536169/original/file-20230706-17-cgavp5.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A specimen of Chinese paddlefish, <em>Psephurus gladius</em> (top), with other types of fish at the Tianjin Natural History Museum.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:A_specimen_of_Psephurus_gladius_with_a_few_sort_of_fish,_Tianjin_Natural_History_Museum.jpg">Calliston3/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The importance of very large fish to freshwater ecosystems has been woefully understudied. Many giant freshwater fish are <a href="https://www.discoverwildlife.com/animal-facts/apex-predators-what-they-are/">apex predators</a> that can have profound effects on the ecosystems in which they live by keeping their prey populations in check and maintaining biodiversity.</p>
<h2>What’s killing off the megafish</h2>
<p>The decline of giant freshwater fish is due to <a href="https://www.nationalgeographic.com/environment/article/freshwater-threats">human impacts</a>, such as overfishing, dam building and climate change.</p>
<p>Large fish are disproportionately targeted by fishing. Since many of these species are slow to mature, they may never reach the age to reproduce. Dam building is <a href="https://news.mongabay.com/2020/07/migratory-freshwater-fish-in-peril-as-report-shows-population-plunge/">another major threat</a>, because large fish often need to make long migrations to complete their life cycles, and a new dam can block their migration paths.</p>
<figure class="align-center ">
<img alt="Two men stand beside a giant fish much longer than they are. On its side, its body is as high as a man's knee." src="https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536229/original/file-20230707-16-znrg45.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This 646-pound Mekong giant catfish was caught in 2005.</span>
<span class="attribution"><span class="source">Suthep Kritsanavarin</span></span>
</figcaption>
</figure>
<p>In the Mekong, where more giant fish species are found <a href="https://doi.org/10.1641/0006-3568(2005)055%5B1041:OOIW%5D2.0.CO;2">than in any other river</a>, climate change is causing more severe droughts and disrupting the monsoon seasons that govern the river’s essential flood regime.</p>
<p>There are signs that interest in freshwater species is gaining momentum, including increasing calls to explicitly include freshwater ecosystems in the <a href="https://theconversation.com/protecting-30-of-earths-surface-for-nature-means-thinking-about-connections-near-and-far-180296">30x30 initiative</a>, a global effort to set aside 30% of land and sea area for conservation by 2030. So far, however, <a href="https://www.nationalgeographic.com/environment/article/inside-the-plan-to-save-some-of-the-biggest-freshwater-fish">conservation efforts</a> to protect endangered giant freshwater fish species are mostly regional. </p>
<h2>Alligator gars and sturgeon make a comeback</h2>
<p>Although the outlook for most giant fish remains grim, some species, like <a href="https://doi.org/10.1242/jeb.00887">the air-breathing arapaima</a> in South America, may be bucking the trend.</p>
<p>The arapaima, a torpedo-shaped giant that can grow to lengths of more than 12 feet, has long been overharvested by fishers in the Amazon, where it’s known as the Amazonian cod. But <a href="https://freshwaterblog.net/2019/01/14/community-based-conservation-of-arapaima-and-giant-turtles-in-the-amazon-basin/">stricter fishing regulations</a> introduced by Indigenous communities appear to have led to populations’ rebounding in many places.</p>
<figure class="align-center ">
<img alt="A large fish with a flat head and scales that look like shell imprints in sand swims underwater." src="https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536190/original/file-20230707-17-17u4zh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Arapaima, found in South America, are often over 200 pounds and can grow much larger.</span>
<span class="attribution"><span class="source">Zeb Hogan</span></span>
</figcaption>
</figure>
<p>In the United States, <a href="https://tpwd.texas.gov/fishboat/fish/management/alligator-gar/">the alligator gar</a>, another air-breathing megafish, was once largely considered a “trash fish” thought to devour game fish, so it was systematically exterminated from much of its southern range. But then scientists began to study the species and found it was an important contributor to ecosystem functions. Today, alligator gar populations have <a href="https://www.texasmonthly.com/travel/all-hail-the-alligator-gar-a-giant-and-primordial-river-monster/">bounced back</a> in rivers like the Trinity in Texas.</p>
<p>A similar case involves the <a href="https://www.nationalgeographic.com/animals/fish/facts/lake-sturgeon">lake sturgeon</a>, one of the few true freshwater sturgeons, whose populations in Wisconsin have benefited from <a href="https://dnr.wisconsin.gov/topic/Fishing/sturgeon/SturgeonInlandFishery.html">long-term conservation efforts</a> and science-driven management that includes strictly regulated seasonal recreational fishing.</p>
<h2>Protecting the giants of the Mekong</h2>
<p>Back in Cambodia, our Wonders of the Mekong project is raising public awareness about the plight of the megafish, and we are working closely with local fishers to encourage them to protect threatened species.</p>
<p>In an example of those efforts’ paying off, fishers in early 2023 caught a <a href="https://www.wwf.org.kh/projects_and_reports2/endangered_species/fish/mekong_giant_catfish/">Mekong giant catfish</a> weighing more than 200 pounds. Instead of killing it and selling the meat for a sizable profit, the fishers decided to release the fish in an elaborate ceremony in which it was sprinkled with flowers before it was let go.</p>
<figure class="align-center ">
<img alt="People fill the prow of a large fishing boat as people release a very big fish into the water below from a tarp." src="https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536150/original/file-20230706-16-yjmdkg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The giant catfish released into the Mekong River with a ceremony in early 2023.</span>
<span class="attribution"><span class="source">Wonders of the Mekong</span></span>
</figcaption>
</figure>
<p>In recent months, our project has also reintroduced into the Mekong rare giant catfish that were captured as young fish and raised in Cambodia, and giant barb, another critically endangered megafish species that historically has grown to 600 pounds. </p>
<p>While giant freshwater stingray numbers have plummeted in other parts of its native Southeast Asian range, the population appears to be relatively robust in the upper stretches of the Mekong River in Cambodia where the record ray was discovered. Data collected from that female, and reported <a href="https://www.mdpi.com/2073-4441/15/10/1936">in a study</a> I co-authored, shows it is staying in much the same location, leading researchers to believe the area could be an important refuge for the stingrays and possibly other megafish.</p>
<figure class="align-center ">
<img alt="A close up of the head of a sting ray shows the large breathing openings and smaller eyes." src="https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536148/original/file-20230706-15-a89wwd.JPEG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Giant freshwater stingray like this one can breath air.</span>
<span class="attribution"><span class="source">Stefan Lovgren</span></span>
</figcaption>
</figure>
<p>Long-standing plans by the Cambodian government to build two large dams on this section of the river appear to have been scrapped, at least for now. At the end of 2022, the government instead put forth <a href="https://thediplomat.com/2022/12/cambodia-seeks-unesco-world-heritage-status-to-protect-a-mekong-biodiversity-hotspot/">a proposal</a> to turn the biodiverse stretch of the river, which is also home to a critically endangered population of Irrawaddy river dolphins, into a <a href="https://whc.unesco.org/en/faq/19">UNESCO World Heritage site</a>.</p>
<p>While the record stingray is big, it might not be the largest of this species of ray in the Mekong. Local fishers speak of rays growing up to 200 pounds heavier.</p>
<p>It’s also possible the giant stingray is not the largest freshwater fish species. Research on the arapaima, for example, suggests it could grow <a href="https://www.sciencedirect.com/science/article/abs/pii/S0165783620302095">as big, or even bigger</a>, in places like Guyana. But, as Hogan says, “It’s not about finding the biggest fish. It’s about learning more about these amazing creatures to figure out how to better protect them.”</p><img src="https://counter.theconversation.com/content/207472/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stefan Lovgren is a research scientist at the University of Nevada, Reno, and affiliated with the Wonders of the Mekong research project, which is financed by USAID</span></em></p>Freshwater megafish numbers have fallen by 94%, according to one study.Stefan Lovgren, Research Scientist in River Ecosystems, University of Nevada, RenoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2037392023-07-10T21:05:54Z2023-07-10T21:05:54ZClimate change is transforming our oceans. Can fisheries management adapt?<figure><img src="https://images.theconversation.com/files/523608/original/file-20230501-28-hwh67t.jpg?ixlib=rb-1.1.0&rect=251%2C305%2C5739%2C3682&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In the 1990s, the northern cod population in Newfoundland, Canada, collapsed by more than 99 per cent.</span> <span class="attribution"><span class="source">(Ricardo Resende/Unsplash)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/climate-change-is-transforming-our-oceans-can-fisheries-management-adapt" width="100%" height="400"></iframe>
<p>Newfoundland’s northern cod was once thought to be an inexhaustible resource. In fact, much of the province’s history and culture continues to be linked with this iconic species. But in the 1990s, the northern cod population here <a href="https://doi.org/10.1890/1051-0761(1997)007%5B0091:WDFSCT%5D2.0.CO;2">collapsed by more than 99 per cent</a> along with <a href="https://doi.org/10.1098/rsos.170215">other groundfish species</a>.</p>
<p>In addition to prolonged overfishing, this decline has been attributed to the <a href="https://doi.org/10.5194/essd-13-1807-2021">ecosystem’s decreased productivity during a 15-year-long cold period in the Canadian Atlantic</a>, resulting in <a href="https://doi.org/10.1016/j.fishres.2021.106180">less food availability for cod</a> and other groundfish. The northern cod collapse brought about a fishing moratorium in 1992, putting more than <a href="https://canadiangeographic.ca/articles/cod-moratorium-how-newfoundlands-cod-industry-disappeared-overnight/">30,000 Newfoundlanders out of work</a>. </p>
<p>In the following years, cod and other groundfish were much slower to recover than expected. Meanwhile, invertebrates such as <a href="https://doi.org/10.1007/s11160-014-9349-7">snow crab</a> and <a href="https://doi.org/10.2960/J.v27.a5">northern shrimp</a> boomed. The soaring snow crab and shrimp fisheries fetched as much as ten times the price of cod. </p>
<p>Managing fisheries in ecosystems that undergo dramatic shifts in species dominance can be challenging — they are a moving target. As we explore ways to sustainably manage the fisheries of these moving targets, we need to have a flexible and adaptable management system, especially in times of a <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/">rapidly changing climate that is altering marine ecosystems globally</a>. </p>
<h2>Challenges for fisheries science and management</h2>
<p>The Newfoundland story highlights a challenge for fisheries science and management. <a href="https://www.dfo-mpo.gc.ca/fisheries-peches/commercial-commerciale/atl-arc/2023/snow-crab-crabe-neige-tac-2023-eng.html">Fisheries catch quotas set by Fisheries and Oceans Canada</a> relative to the baseline of the population of the specific fish species — also referred to as reference points. </p>
<p>Reference points serve as standards to assess the present condition of a fish stock in relation to a preferred (or undesired) state. They guide setting sustainable limits of fishing quotas.</p>
<p>Quotas are set to prevent overfishing. Typically, fisheries targets aim to keep population biomass — the overall population size — at about 50 per cent of the unfished population baseline. In general, a fish population is most productive when it is at this level. </p>
<figure class="align-center ">
<img alt="A lot of fish in in a fishing boat" src="https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=484&fit=crop&dpr=1 754w, https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=484&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/523612/original/file-20230501-28-dnw6ms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=484&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Atlantic cod removed from fishing boats in Newfoundland.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/dkeats/5645779248/in/album-72157626428355069/">(Derek Keats/flickr)</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Within fisheries management agencies in Canada, there has been a move to implement <a href="https://www.dfo-mpo.gc.ca/reports-rapports/regs/sff-cpd/precaution-back-fiche-eng.htm">“limit reference points”</a>. </p>
<p>These limit reference points mark the fine line between cautious and critical levels. If the fish stock falls below the limit, there is risk of serious harm to a fished population. Limit reference points are typically set between 20 to 30 per cent of the unfished biomass baseline. </p>
<p>If biomass falls below the limit, it is prudent to close the fishery until it recovers — although, <a href="https://doi.org/10.1139/facets-2020-0006">in Canada, this decision is subject to ministerial discretion</a>. </p>
<p>However, setting these reference points can be challenging when ecosystems are highly dynamic over time, <a href="https://essd.copernicus.org/articles/13/1807/2021/essd-13-1807-2021-discussion.html">as seen in Newfoundland</a>. In a highly dynamic ecosystem, reference points based on outdated productivity regimes are ineffective.</p>
<p>Sometimes initial baselines of unfished biomass are no longer achievable under a new productivity pattern. Accounting for changes in productivity can help prevent fish stocks from collapsing.</p>
<h2>A cutting-edge solution</h2>
<p>The challenge of managing fisheries in highly dynamic ecosystems has a new solution — “dynamic reference points.” <a href="https://doi.org/10.1016/j.fishres.2018.11.028">Dynamic reference points consider changes in the ecosystem and fish population productivity</a> to inform sustainable fisheries targets and to set limits to avoid overfishing. </p>
<p>Dynamic reference points are a way to adapt fisheries management to environmental changes. For example, if a fish stock is less productive than it was historically and has a lower population size, dynamic reference points account for this change.</p>
<p>By accounting for the influence of the environment and other species on fish stocks, this approach provides a bridge between fisheries management of individual species and <a href="https://www.dfo-mpo.gc.ca/reports-rapports/regs/sff-cpd/ecosys-back-fiche-eng.htm">an ecosystem-based fisheries management</a>. </p>
<p>Traditional fisheries reference points assume the environment and ecosystem are stable. This might be reasonable in some cases, but as <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/">climate change is shifting species ranges and causing greater changes in environmental conditions</a>, ensuring reference points reflect these changes is important to sustainably manage fisheries. </p>
<h2>Overcoming barriers</h2>
<p>The uptake of this cutting-edge approach for fisheries management practices is not without barriers. Based on <a href="https://doi.org/10.1139/facets-2022-0216">our global expert survey</a>, just published, only 10 per cent of reported fisheries used dynamic reference points.</p>
<p>Our study found that institutional inertia and uncertainty about whether changes in ecosystems or fish stock productivity are lasting or not are some of the main barriers to the implementation of these dynamic reference points.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A bar graph of the barriers to sustainable fisheries tool" src="https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/523610/original/file-20230501-28-jmw3na.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The main barriers to implementing dynamic reference points in fisheries management as identified by survey participants.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1139/facets-2022-0216">(Tyler Eddy)</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Government institutions that manage fisheries can be slow to adopt new approaches. This may benefit fishing industries, as they know what to expect. However, as <a href="https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/">climate change increasingly affects marine ecosystems and the fisheries they support</a>, dynamic reference points provide a solution to adapt to these changes. </p>
<p>Overcoming the barriers to implementation of dynamic reference points is key for fisheries management agencies to effectively respond to highly dynamic ecosystems. While uncertainty about if changes in ecosystems or fish populations are lasting might never be removed, implementing dynamic reference points may promote early detection of — and rapid response to — those changes. </p>
<p>Ultimately, this can help prevent devastating collapses in species such as the northern cod of Newfoundland.</p><img src="https://counter.theconversation.com/content/203739/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tyler Eddy receives funding from the Ocean Frontier Institute, Fisheries & Oceans Canada, and the Natural Sciences and Engineering Research Council of Canada. </span></em></p><p class="fine-print"><em><span>Andrea Bryndum-Buchholz receives funding from the Ocean Frontier Institute.</span></em></p>Having a flexible and adaptable management system is necessary to sustainably manage fisheries, especially in times of a rapidly changing climate.Tyler Eddy, Research Scientist in Fisheries Science, Memorial University of NewfoundlandAndrea Bryndum-Buchholz, Postdoctoral Researcher in Marine Ecology and Climate-Impact Sciences, Memorial University of NewfoundlandLicensed as Creative Commons – attribution, no derivatives.