tag:theconversation.com,2011:/global/topics/tilapia-35742/articlesTilapia – The Conversation2024-02-06T14:27:03Ztag:theconversation.com,2011:article/2216552024-02-06T14:27:03Z2024-02-06T14:27:03ZMicroplastics found in Nile River’s tilapia fish: new study<figure><img src="https://images.theconversation.com/files/570625/original/file-20240122-15-ncnbn9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A fisherman on the River Nile.</span> <span class="attribution"><span class="source">Khaled Desouki/AFP via Getty Images</span></span></figcaption></figure><p>The Nile is one of the world’s most famous rivers. It’s also Africa’s most important freshwater system. <a href="https://www.rti.org/impact/nile-river-basin-initiative#:%7E:text=The%20longest%20river%20in%20the,%2C%20Rwanda%2C%20Burundi%2C%20Tanzania%2C">About 300 million people</a> live in the 11 countries it flows through. Many rely on its waters for agriculture and fishing to make a living. </p>
<p>The Nile’s two main tributaries, the Blue Nile and the White Nile, come together in Sudan’s capital city, Khartoum. This industrial hub has <a href="https://worldpopulationreview.com/world-cities/khartoum-population">grown rapidly over the past few decades</a>.</p>
<p>The Nile is not immune to the same pollutants that affect rivers all over the world. Plastic debris is of particular concern. Over time plastics break down into smaller pieces known as microplastics. These are tiny plastic particles with a maximum size of five millimetres, all the way down to the nanoscale. <a href="https://www.nature.com/articles/s41467-023-40501-9">Recent research</a> found that</p>
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<p>rivers are modelled to export up to 25,000 tons of plastics from their sub-basins to seas annually. Over 80% of this amount is microplastic.</p>
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<p>This has huge negative consequences for biodiversity and the climate. As microplastics degrade, scientists have found, they <a href="https://www.sciencedirect.com/science/article/abs/pii/S2213343722019200">produce greenhouse gases</a>. Airborne microplastics may influence the climate by scattering and absorbing solar and terrestrial radiation, <a href="https://www.wired.com/story/microplastics-may-be-cooling-and-heating-earths-climate/">leading to atmospheric warming or cooling</a> depending on particle size, shape and composition. It also negatively affects <a href="https://www.undp.org/kosovo/blog/microplastics-human-health-how-much-do-they-harm-us">animal and human health</a>. Microplastics <a href="https://pubs.acs.org/doi/10.1021/envhealth.3c00052">have been shown</a> in laboratory studies to be toxic to animals and cells. </p>
<p>Much of the research about microplastics in African waters has focused on marine and coastal areas. To address this gap, I <a href="https://www.cell.com/heliyon/pdf/S2405-8440(23)10601-3.pdf">conducted a study</a> to assess the presence of microplastics in the River Nile in Khartoum. My students and I tested for the presence of microplastics in Nile tilapia. This popular African freshwater fish species <a href="https://www.mdpi.com/2071-1050/14/2/974">forms the basis</a> of commercial fisheries in many African countries, including Sudan.</p>
<p>The results do not make for happy reading. In the 30 freshly caught fish we surveyed, we found a total of 567 microplastic particles. This shows that the River Nile is contaminated with microplastics that can be consumed or absorbed in various ways by the tilapia and other aquatic organisms.</p>
<h2>Our sample</h2>
<p>The fish used in our study were caught just after the meeting point of the two Niles, known in Arabic as Al-Mogran. </p>
<p>We visited the Al-Mawrada fish market in the Omdurman area, which is also alongside the Nile. All 30 specimens we bought were freshly caught. </p>
<p>We dissected the fish to remove their digestive tracts. The individual tracts were treated so they would digest any organic matter they contained without interfering with the analysis of microplastics. The resulting solution was subject to another extraction procedure and we then conducted physical and chemical analyses.</p>
<p>Every specimen had microplastics in its digestive tract.</p>
<p>The number ranged from as few as five to as many as 47 particles per single fish. In total we identified 567 particles. This is high compared to <a href="https://www.sciencedirect.com/science/article/abs/pii/S0045653520331659">studies</a> that have <a href="https://www.researchsquare.com/article/rs-2430557/v1">reported microplastics</a> in tilapia species in other rivers and lakes. There is, as yet, no global guideline or standard for what might be an “acceptable” number.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/fish-in-a-major-south-african-river-are-full-of-microplastics-186017">Fish in a major South African river are full of microplastics</a>
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<h2>Shape, size and colour</h2>
<p>We detected different sizes of microplastics (0.04mm to 4.94mm), shapes (fibres, fragments, films, foams and pellets) and colours. The most common were very small (less than 1mm), fibrous – they appear slender and elongated – and coloured (dyed).</p>
<p>These characteristics make sense because of how fish and other aquatic organisms feed. Nile tilapia are versatile feeders: they consume a variety of organisms including phytoplankton, aquatic plants, invertebrates, detritus, bacterial films, as well as other fish and fish eggs. That puts them at a high risk of ingesting microplastics.</p>
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Read more:
<a href="https://theconversation.com/lagos-beaches-have-a-microplastic-pollution-problem-128133">Lagos beaches have a microplastic pollution problem</a>
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</em>
</p>
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<p>Nile tilapia are also more likely to consume particles that are within a similar size range as their natural prey, as well as the same shape and colour.</p>
<p>Smaller microplastics are especially good carriers for other pollutants such as heavy metals, resulting in additional health risks. Their small size also makes it easier for them to move into organs like the liver. Studies have found microplastics in the tissues, muscles, livers, blubber and lungs of other <a href="https://www.sciencedirect.com/science/article/abs/pii/S0025326X15002581">aquatic</a> as well as <a href="https://www.sciencedirect.com/science/article/pii/S026974912301254X">marine mammal species</a>.</p>
<p>Fibres, the most dominant shape found in our specimens, stay in the intestine for longer than other microplastic shapes. This, too, can lead to health problems for the fish. Coloured microplastics contain dyes, many of which <a href="https://link.springer.com/article/10.1007/s13762-023-05168-1">contain toxic chemicals</a>. </p>
<p>This all has serious implications for human health, as people catch and eat the fish, which introduces those <a href="https://www.intechopen.com/chapters/86342">microplastics and associated chemicals into their bloodstreams</a>.</p>
<h2>Pollution sources</h2>
<p>Where does all this plastic originate? For starters, 65% of plastic waste in Khartoum is disposed of in <a href="https://www.ijsr.net/archive/v4i3/SUB151879.pdf">open dumps</a>. From there, it contaminates water bodies and other parts of the environment.</p>
<p>The city’s wastewater treatment system is ineffective. The three wastewater treatment plants in Khartoum state, Karary, Wd-Daffiaa and Soba, are outdated and <a href="https://www.sciencedirect.com/science/article/abs/pii/S2214785321069704?via%3Dihub">do not meet local and international standards</a>. That means untreated effluent from domestic, industrial and agricultural activities is another probable source of microplastic pollution.</p>
<p>There are also countless recreational sites along the River Nile in Khartoum. The Nile Street is the most popular in the capital city, hosting water sports, restaurants, cafes, clubs, event venues and hotels, as well as the tea ladies (women who serve hot beverages from makeshift mobile cafes along the banks of the river). However, waste disposal and collection practices are sorely lacking, so plastic litter from these leisure activities leaks into the river.</p>
<h2>No easy fix</h2>
<p>Tackling microplastic pollution is not easy. It will require technological advances, as well as the collective efforts of consumers, producers, governments and the scientific community.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/plastic-pollution-in-nigeria-is-poorly-studied-but-enough-is-known-to-urge-action-184591">Plastic pollution in Nigeria is poorly studied but enough is known to urge action</a>
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<p>As consumers, we need to change our behaviour around plastic products, especially single-use plastics. For example, opt for fabric shopping bags instead of plastic bags; use glass and metal containers. Recycling is also important.</p>
<p>Governments must enforce waste management regulations and improve waste management practices, as well as helping to improve public awareness. Strategies and policies must explicitly feature microplastics.</p>
<p>Scientists can not only fill the knowledge gaps around microplastics. Communicating scientific findings is crucial; so too is developing innovations to protect against microplastics and their harmful effects.</p>
<p><em>I would like to thank and acknowledge my student Hadeel Alamin, who conducted this study with me.</em></p><img src="https://counter.theconversation.com/content/221655/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The project was funded by the Royal Society – UK.</span></em></p>The River Nile is contaminated with microplastics.Dalia Saad, Researcher, School of Chemistry, University of the Witwatersrand, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1519042021-03-26T12:24:08Z2021-03-26T12:24:08ZFarming fish in fresh water is more affordable and sustainable than in the ocean<figure><img src="https://images.theconversation.com/files/391754/original/file-20210325-15-bts8vt.jpg?ixlib=rb-1.1.0&rect=0%2C16%2C5503%2C3650&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Jeremiah Kiarie rounds up tilapia at Green Algae Highland fish farm in central Kenya on April 29, 2017.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/jeremiah-son-of-fish-farmer-william-kiarie-rounds-up-news-photo/696599724">Tony Karumba/AFP via Getty Images</a></span></figcaption></figure><p>A tidal wave of interest is building in farming the seas. It’s part of a <a href="https://theconversation.com/blue-economy-how-a-handful-of-companies-reap-most-of-the-benefits-in-multi-billion-ocean-industries-153165">global rush</a> to exploit oceanic resources that’s been dubbed the “<a href="https://theconversation.com/blue-acceleration-our-dash-for-ocean-resources-mirrors-what-weve-already-done-to-the-land-130264">blue acceleration</a>.” </p>
<p>Optimistic projections say that smart mariculture – fish farming at sea – could <a href="https://doi.org/10.1038/s41586-020-2616-y">increase ocean fish and shellfish production</a> by 21 million to 44 million metric tons by 2050, a 36%-74% jump from current yields. Other estimates suggest that an ocean aquaculture area <a href="https://theconversation.com/how-a-tiny-portion-of-the-worlds-oceans-could-help-meet-global-seafood-demand-82680">the size of Lake Michigan</a> might produce the same amount of seafood as all of the world’s wild-caught fisheries combined. </p>
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<img alt="" src="https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/369797/original/file-20201117-13-180ibt9.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><strong><em>This story is part of <a href="https://theconversation.com/uk/topics/oceans-21-96784">Oceans 21</a></em></strong>
<br><em>Our series on the global ocean opened with <a href="https://oceans21.netlify.app/">five in depth profiles</a>. Look out for new articles on the state of our oceans in the lead up to the UN’s next climate conference, COP26. The series is brought to you by The Conversation’s international network.</em></p>
<p>Our work as interdisciplinary researchers studying <a href="https://worldfishcenter.org/strategy-2030/">aquatic</a> <a href="https://scholar.google.com/citations?user=gs3YPlEAAAAJ&hl=en">food</a> <a href="https://www.researchgate.net/profile/Wenbo-Zhang-18">systems</a> shows that these claims <a href="https://doi.org/10.1038/s41467-020-19679-9">exaggerate mariculture’s true potential</a>, and that increasing mariculture in a sustainable way is fraught with challenges. </p>
<p>We see <a href="https://theconversation.com/let-them-eat-carp-fish-farms-are-helping-to-fight-hunger-90421">freshwater fish farms</a> as a better way to help fight hunger and bolster food security. In our view, governments, funders and scientists should focus on improving aquaculture on land to help meet the <a href="https://sdgs.un.org/goals">United Nation Sustainable Development Goals</a>. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/-yhtVSW65Ag?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In recent years Bangladesh has become a leader in low-cost, sustainable aquaculture.</span></figcaption>
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<h2>Questionable assumptions</h2>
<p>Ocean aquaculture advocates often cite limited supplies of wild-caught fish and call for <a href="https://www.weforum.org/agenda/2017/10/how-aquaculture-can-feed-the-world-and-save-the-planet-at-the-same-time">cultivating them to feed the world</a>. As they see it, aquaculture on land is limited by scarce land and freshwater resources, while the oceans offer vast areas suitable for farming. </p>
<p>Framed this way, mariculture seems to offer boundless potential to meet future demand for seafood and feed vulnerable populations with <a href="https://www.weforum.org/agenda/2020/05/how-to-build-a-bluer-ocean-economy-after-cobid-19/">little environmental impact</a>. But <a href="https://doi.org/10.1038/s41467-020-19679-9">our research</a> paints a different picture. We see far fewer technical, economic and resource constraints for freshwater aquaculture than for ocean farming, and far greater potential for land-based fish farms to contribute to global food security.</p>
<p>Freshwater aquaculture has grown steadily over the past three decades. Asia is at the center of this boom, accounting for <a href="http://www.fao.org/documents/card/en/c/ca9229en">89% of world aquaculture production</a>, excluding plants. </p>
<p>The most important species groups – carp, tilapia and catfish – are herbivorous or omnivorous, so they don’t need to eat animal protein to thrive. While they may be fed small amounts of fish to speed growth, their mainstay diet consists of inexpensive byproducts of crops like rice, groundnut and soy, as well as natural plankton.</p>
<p>It’s relatively cheap and easy to grow freshwater fish in small earthen ponds. Aquaculture has been an <a href="https://doi.org/10.1016/j.aquaculture.2018.08.077">economic boon</a>, especially in Asia, providing jobs and income for vast numbers of family farms, workers and small businesses. Farmed freshwater fish tend to be an <a href="https://doi.org/10.1016/j.gfs.2017.10.005">affordable staple food</a> for millions of low- and middle-income consumers – and many better-off ones, too. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1362437219651379203"}"></div></p>
<h2>Raising marine fish</h2>
<p>Raising marine fish is a different proposition. The harsh ocean environment makes production risky, and the biology of these species makes many of them difficult and costly to breed and grow. </p>
<p>Most marine aquaculture species are carnivores, so they need other fish as part of their diets. About <a href="https://doi.org/10.1111/faf.12209">20 million metric tons of fish</a> caught each year is used instead to feed farmed fish. It’s a <a href="https://www.seafoodwatch.org/seafood-basics/sustainable-solutions/limit-wild-fish-use-as-feed">contentious environmental and ethical issue</a>, as some of these fish could otherwise be food for humans.</p>
<p>Improvements in technology have reduced, though not eliminated, the amount of fish used in feeds, especially for <a href="https://doi.org/10.1080/10641262.2011.597890">farmed salmon</a>. It now takes <a href="https://doi.org/10.1016/j.aqrep.2019.100216">half as much fresh fish</a> to raise salmon as it did 20 years ago. </p>
<p>These innovations were achieved through <a href="https://doi.org/10.1080/13657305.2019.1632391">massive investments</a> by the Norwegian government and the industry, dating back to the 1970s. Research focused on genetic improvement, nutrition and production systems, and it’s paid off. Farmed salmon now accounts for <a href="http://www.fao.org/fishery/statistics/global-production/en">45% of all fish farmed from the sea</a>. </p>
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<a href="https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Floating salmon pens off Canadian coast." src="https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/391609/original/file-20210325-17-1r67r2x.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>
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<span class="caption">Grieg Seafood operates a salmon farm in Clio Channel, Broughton Archipelago, British Columbia, Canada, in partnership with the Tlowitsis First Nation.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/2jnT5gB">David Stanley/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>However, it’s unlikely that other less popular fish, like grouper, sea bass or cobia, will be as thoroughly researched or farmed with the same efficiency. The market is too small. </p>
<p>For a land-based analogy, think of chickens. Like salmon, they have long been the focus of <a href="https://doi.org/10.1098/rsos.180325">intensive research and development</a>. As a result, they now grow to market size in just 45 days. On the other hand, the guinea fowl – a chickenlike bird raised for specialty markets – has undergone limited selective breeding, develops slowly and yields far less meat, making it more costly to raise and more expensive to buy. </p>
<h2>Farming the open ocean</h2>
<p>Marine fish farming is currently done in sheltered bays and sea lochs. But there is <a href="https://doi.org/10.1073/pnas.1808737115">growing interest</a> in a new high-tech method that raises fish in huge submersible cages anchored far from land in the open ocean. It’s risky business, with high operating costs. Expensive infrastructure is vulnerable to intense storms. </p>
<p>To be successful, offshore farms will need to grow high-priced fish such as bluefin tuna. And they will need to operate at industrial scale, like SalMar’s massive “Ocean Farm” in Norway, which has capacity for <a href="https://salmonbusiness.com/salmars-gigantic-ocean-farm-gears-up-for-harvest/">1.5 million fish</a>.</p>
<p>While open-ocean mariculture may be technically feasible, its economic viability is questionable. Pilot projects in Norway, <a href="https://www.marinelink.com/news/aquaculture-inside-de-maas-offshore-fish-483165">China</a> and the <a href="https://e360.yale.edu/features/can-deepwater-aquaculture-avoid-the-pitfalls-of-coastal-fish-farms">U.S.</a> are not yet commercially successful. And though there is strong global demand for salmon, other species like grouper have small niche markets. They are likely to remain specialized high-end products because of steep production costs. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Boats move a 100-foot-tall circular pen through ocean waters." src="https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/391758/original/file-20210325-19-1enkjzx.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">A tugboat tows an offshore ocean farming facility in Qingdao, China, on June 14, 2017.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/an-offshore-ocean-farming-facility-ocean-farm-1-is-towed-by-news-photo/696148000">Visual China Group via Getty Images</a></span>
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<h2>Freshwater alternatives</h2>
<p>Human population is growing fastest in <a href="https://www.un.org/development/desa/publications/world-population-prospects-2019-highlights.html">Africa</a>, and incomes are rising most rapidly in <a href="https://www.weforum.org/agenda/2019/12/asia-economic-growth/">Asia</a>. Most additional future demand for fish will come from low- and middle-income consumers in these regions. Farming tilapia and catfish is already becoming more popular in Egypt and both West and East Africa. </p>
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<p>Meanwhile, total seafood consumption in high-income countries <a href="http://www.fao.org/3/I9540EN/i9540en.pdf">has plateaued</a> since 2000. But even in these countries, demand for farmed freshwater fish is growing because it’s an affordable source of protein. In the U.S., tilapia, <a href="https://www.seafoodhealthfacts.org/description-top-commercial-seafood-items/pangasius">pangasius</a> (freshwater catfish) and channel catfish are the fourth-, sixth- and eighth-most-<a href="https://aboutseafood.com/about/top-ten-list-for-seafood-consumption/">consumed</a> seafood items.</p>
<p>Offshore mariculture might one day produce luxury fish that generate profits for a few large investors. But we believe freshwater aquaculture will continue to feed far more people and benefit many more farmers and small businesses. </p>
<p>Investments in selective breeding, disease control and farm management through public-private partnerships can create a more sustainable aquaculture industry, reducing the amount of land, freshwater and feed used to grow fish while increasing productivity. For more inclusive and sustainable development, we believe governments and funders should prioritize raising fish on land.</p><img src="https://counter.theconversation.com/content/151904/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ben Belton shares a joint appointment with WorldFish as Global Lead for Social and Economic Inclusion</span></em></p><p class="fine-print"><em><span>Dave Little receives funding from, and works on a voluntary basis for, various organisations supporting knowledge development and promotion of aquaculture. He has interests in a commercial tilapia company.</span></em></p><p class="fine-print"><em><span>Wenbo Zhang 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>Aquaculture is a growing source of healthy protein for millions of people around the world, but there are big differences between farming fish on land and at sea.Ben Belton, Associate Professor of International Development, Michigan State UniversityDave Little, Professor of Aquatic Resources Development, University of StirlingWenbo Zhang, Lecturer in Fisheries and Life Science, Shanghai Ocean UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/904212018-03-08T11:43:59Z2018-03-08T11:43:59ZLet them eat carp: Fish farms are helping to fight hunger<figure><img src="https://images.theconversation.com/files/205503/original/file-20180208-180844-1db2u8.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Farmed fish like these carp now make an important contribution to global food security.</span> <span class="attribution"><span class="source">Ben Belton</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Over the past three decades, the global aquaculture industry has risen from obscurity to become a critical source of food for millions of people. In 1990, only 13 percent of world seafood consumption was farmed; by 2014, aquaculture was providing <a href="http://www.fao.org/3/a-i3720e.pdf">more than half</a> of the fish consumed directly by human beings. </p>
<p>The boom has made farmed fish like shrimp, tilapia and pangasius catfish – imported from countries such as Thailand, China and Vietnam – an increasingly common sight in European and North American supermarkets. As a result, much research on aquaculture has emphasized production for export. </p>
<p>This focus has led scholars to question whether aquaculture contributes to the <a href="https://www.wfp.org/node/359289">food security</a> of poorer people in producing countries. Many have concluded <a href="https://doi.org/10.1016/j.ocecoaman.2006.06.001">it does not</a>. Meanwhile, the industry’s advocates often emphasize the potential for small-scale farms, mainly growing fish for home consumption, to <a href="http://www.aquaculturewithoutfrontiers.org/">feed the poor</a>. Farms of this kind are sometimes claimed to account for <a href="http://www.fao.org/fileadmin/user_upload/hlpe/hlpe_documents/HLPE_S_and_R/HLPE_2014_Sustainable_Fisheries_and_Aquaculture_Summary_EN.pdf">70 to 80 percent</a>
of global aquaculture production. </p>
<p>Our research shows that both of these perspectives are wildly out of sync with current developments. In fact, the vast majority of farmed fish is consumed in the same developing countries where it is produced, and is widely accessible to poorer consumers in these markets. Most of it comes from a dynamic new class of small- and medium-scale commercial farms, the existence of which is rarely recognized. To understand the potential of aquaculture to feed the world, researchers and consumers need to appreciate how dynamic this industry is.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205506/original/file-20180208-180805-1x8ipy5.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">Farming pangasius catfish for export in Vietnam.</span>
<span class="attribution"><span class="source">Ben Belton</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Farmed fish is a critical food source</h2>
<p>Fish is a rich source of vitamins, minerals, essential fatty acids and high-quality protein. It plays a <a href="https://link.springer.com/article/10.1007/s12571-015-0427-z">particularly important role</a> in the diets of billions of consumers in low- and middle-income countries. Many of these people are poor, malnourished and unable to afford alternative nutrient-rich foods such as fruit, eggs and meat. </p>
<p>Throughout human history most of the fish people eat has been captured from oceans, rivers and lakes. But the total quantity of fish harvested from these sources <a href="http://dx.doi.org/10.1038/ncomms10244">peaked in the mid-1990s</a> due to overfishing and environmental degradation. Demand for seafood has continued to increase since this time, as urbanization and average incomes have risen globally. Aquaculture is filling the gap. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=392&fit=crop&dpr=1 600w, https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=392&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=392&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=493&fit=crop&dpr=1 754w, https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=493&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/206664/original/file-20180215-131038-7vnqvp.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=493&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 total of wild fish capture and aquaculture production (million metric tons).</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/World_fisheries_production#/media/File:Global_total_fish_harvest.svg">Construct, data from FAO</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Overemphasis on exports</h2>
<p>Academic research on aquaculture has focused predominantly on internationally traded species such as shrimp, salmon, and Vietnamese pangasius. These three fish account for less than 10 percent of global farmed fish production, but are the focus of <a href="http://dx.doi.org/10.1111/geoj.12035">the majority of social science publications</a> on aquaculture. This bias reflects the priorities and concerns of developed countries that fund research, as well as civil society organizations that work to promote sustainable aquaculture production through international trade.</p>
<p>Because they assume that this small group of internationally traded species is representative of global aquaculture, many scholars believe that fish farmed in developing nations is <a href="http://dx.doi.org/10.1038/534317a">mainly exported to wealthy countries</a>. The literature also suggests that fish farmers find it most profitable to grow species with a <a href="http://dx.doi.org/10.1111/jfb.12187">high market value</a>, generating little benefit for poorer consumers.</p>
<h2>Fact-checking the numbers</h2>
<p>In a <a href="https://doi.org/10.1016/j.gfs.2017.10.005">recent analysis</a> of fish production and trade, we used <a href="http://www.fao.org/fishery/statistics/software/fishstatj/en">data</a> published by the United Nations Food and Agriculture Organization to show that the importance of global trade in farmed seafood has been vastly overstated. We analyzed farmed fish production and exports for 2011 – the most recent year both sets of data were available – for the 10 most important aquaculture producing developing countries, which together account for 87 percent of global aquaculture production and half of the world’s human population. </p>
<p>Our analysis shows that export trade from these countries is relatively insignificant. In fact, we found 89 percent of the fish farmed in these countries remain in their domestic markets. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205507/original/file-20180208-180821-crornh.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">Mobile vendor selling affordable fish in Bangladesh.</span>
<span class="attribution"><span class="source">Ben Belton</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Aquaculture is pro-poor</h2>
<p>But is this fish reaching the poor? To answer this question, we pieced together multiple sources of information on fish prices and fish consumption in these same 10 countries. A consistent pattern emerged: Where the quantity of farmed fish has grown substantially, the real price of farmed fish, adjusted for inflation, has fallen significantly, and the quantity of fish consumed by poorer consumers has grown. </p>
<p>For example, in Bangladesh – one of Asia’s poorest countries – the farmed fish market grew <a href="https://doi.org/10.1016/j.aquaculture.2017.06.006">by a factor of 25</a> in three decades to exceed two million tons in 2015. This growth caused the real price of farmed fish to drop by nine percent from 2000 to 2010, at the same time that wild fish were becoming scarcer and more expensive. Consumption of farmed fish by poorer households – who are particularly sensitive to changes in food prices – increased rapidly over this period, more than offsetting a decline in the quantity of wild fish eaten. </p>
<p>These trends imply that the expansion of fish farming has been <a href="https://doi.org/10.1016/j.worlddev.2014.06.035">good for the poor</a>. Low-income households in the countries that we studied would eat less fish of any kind today, wild or farmed, were it not for the growth of aquaculture. </p>
<h2>A quiet revolution</h2>
<p>So who is producing this fish, and how? The “<a href="https://doi.org/10.1016/j.aquaculture.2017.06.006">quiet revolution</a>” in farmed fish supply has been driven neither by corporate agribusiness nor by tiny backyard farms. Rather, most of aquaculture’s growth over the past three decades has come from a dynamic and increasingly sophisticated segment of small- and medium-sized commercial farms and the myriad businesses that support them by supplying inputs such as feed, logistics and other services.</p>
<p>Rather than focusing on producing expensive species for export markets or wealthy domestic customers, these unsung heroes have focused on growing affordable fish such as carp. Where these species are produced in large quantities, they have become affordable for huge numbers of low- and middle-income consumers close to home. </p>
<p>This transformation has not yet taken hold in many developing countries, particularly in Africa, where access to inexpensive fish could greatly improve food security. By learning from the example of nations where farmed fish supply has boomed, governments and aid organizations can make better targeted investments in infrastructure, institutions, policies and technologies to expand the impact of aquaculture’s quiet revolution.</p><img src="https://counter.theconversation.com/content/90421/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ben Belton receives funding from the United States Agency for International Development, and the Livelihoods and Food Security Trust Fund. </span></em></p><p class="fine-print"><em><span>Dave Little receives funding from Progammes funded by the Department for International Development, UK, and the European Union </span></em></p><p class="fine-print"><em><span>Simon Bush receives funding from the Dutch Scientific Organisation (NWO), Addessium Foundation and Monterrey Bay Seafood Watch Programme.</span></em></p>Many critics say that fish farms mainly sell their output to wealthy countries and don’t provide much benefit to poor people in producing countries. Three aquaculture experts show why this view is wrong.Ben Belton, Assistant Professor of International Development, Michigan State UniversityDave Little, Professor of Aquatic Resources Development, University of StirlingSimon Bush, Professor and Chair of Environmental Policy, Wageningen UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/788612017-06-07T15:30:30Z2017-06-07T15:30:30ZAquaculture in sub-Saharan Africa: small successes, bigger prospects?<figure><img src="https://images.theconversation.com/files/172689/original/file-20170607-11311-1fz7lwl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Almost all production of freshwater fish includes Tilapia.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>If you don’t know what aquaculture is, you’re not alone: a 2009 survey found that a remarkable <a href="http://www.soundinteraxions.co.za/2009AISABenchmarkingSurveyFINAL.pdf.pdf">85% of South Africans</a> had never even heard the term, and most are still unaware of its importance. The situation hasn’t improved much, more people have heard of it but few actually know what it is.</p>
<p>Aquaculture is the aquatic equivalent of agriculture. It involves essentially “growing” animals and plants that live in lakes, rivers or the sea, mostly for human consumption. It has been one of the world’s fastest growing industries in <a href="http://www.fao.org/docrep/003/x8002e/x8002e07.htm">recent decades</a> </p>
<p>In fact today, you’re more likely to be eating “farmed” fish than fish from the wild. But that is not true in South Africa, yet. In 2014 the supply of fish for human consumption from aquaculture exceeded that from wild-caught fisheries for <a href="http://www.fao.org/3/a-i5555e.pdf">the first time</a>. This trend is continuing, as the amount of fish which can be supplied by the traditional fishing industry has reached a plateau, and aquaculture continues to expand at a rapid rate. It’s increasing in those countries with a long tradition of aquaculture, but also in regions where it hasn’t been done before. </p>
<p>As the supply of fish and seafood through fishing becomes less sustainable, the global challenge is to replace it sustainably through aquaculture.</p>
<p>The industry has grown slowly in sub-Saharan Africa. Freshwater fish aquaculture has recently expanded very rapidly in the region from a low base. Marine aquaculture has yet to take off, with only one or two successful examples. As fisheries become more depleted, there’s a growing need and opportunity to develop aquaculture for food. </p>
<p>Shortage of suitable sea space may eventually limit expansion in South Africa, but there are many such sea areas around the continent where marine aquaculture could increase rapidly given the required input of investment and expertise.</p>
<h2>Aquaculture in sub-Saharan Africa</h2>
<p>Most of the world’s aquaculture production takes place <a href="http://www.fao.org/3/a-i5555e.pdf">in Asia</a>, with China (60%), and the top 6 countries – all in Asia – <a href="http://www.fao.org/3/a-i5555e.pdf">produce 86%</a>. The rapid growth rate in aquaculture production over the last quarter of a century in Asian countries is being mirrored in the production of freshwater fish in sub-Saharan Africa.</p>
<p>Only <a href="http://www.fao.org/3/a-i5555e.pdf">550 000 tonnes</a> of aquatic animals were grown in 2014, which is less than 1% of the world production. Almost all of this is of freshwater fish – mostly catfish, Tilapia and Nile Perch. Nigeria and Uganda are the <a href="http://www.fao.org/3/a-i6873e.pdf">region’s leading producers.</a></p>
<p>Marine aquaculture production in Africa is a more depressing story. Just 12 000t of animal production was reported in 2008, dropping to <a href="http://www.fao.org/3/a-i6873e.pdf">10 000t in 2014.</a> Most of this was made up of prawns in Madagascar and Mozambique, and molluscs like abalone, mussels and oysters in South Africa. The drop in output was largely because of the <a href="http://www.responsibleaqua.org/research-programs/ems/">White Spot Syndrome Virus</a> in prawn aquaculture. This has decimated the industry in Mozambique and Madagascar since 2011. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/172687/original/file-20170607-11324-q67l3i.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">South Africa’s main marine aquaculture success story is the [local abalone.</span>
<span class="attribution"><span class="source">Mike Stekoll</span></span>
</figcaption>
</figure>
<p>One long-term marine aquaculture industry in the region is the <a href="https://www.farmafrica.org/us/tanzania/seaweed-farming-in-zanzibar">red seaweeds in Tanzania</a>, with a figure of 13 000t in 2014. The seaweed is not eaten directly, but is exported dry for overseas production of the colloid carrageenan. This is a type of jelly which is used mostly in the food industry as a thickening, gelling, stabilising and suspending agent in milk and water-based foods. The income from cultivation of these seaweeds is low from a global perspective, but makes a significant difference to household incomes in some areas, particularly in Zanzibar. </p>
<p>In South Africa, you’re almost certainly eating aquaculture products if you order local oysters, mussels and trout, or imported salmon, prawns, or seaweed in sushi.</p>
<h2>South African marine aquaculture</h2>
<p>The country’s main marine aquaculture success story is the <a href="http://www.engineeringnews.co.za/article/abalone-spearheading-sas-aquaculture-sector-2016-03-09/rep_id:4136">local abalone Haliotis midae (“perlemoen”)</a>.
It began in the 1990s, and now around 1500t are produced annually representing over 90% of the value of <a href="http://www.engineeringnews.co.za/article/sa-moving-to-secure-its-share-of-world-aquaculture-growth-2013-07-26-1">South African marine aquaculture.</a> South African abalone is not grown on ropes, rafts or in cages in the sea or sheltered bays/estuaries unlike most of the global marine aquaculture. It’s a high value product, grown by pumping large amounts of seawater into tanks on land. </p>
<p>A large abalone farm pumps over 10 million litres of seawater per hour, with electricity for pumping a major cost component. Such infrastructure is only economically feasible with a high value product. Most South African farmed abalone is flown live or exported in cans to China. </p>
<p>The two main success stories in marine aquaculture in sub-Saharan Africa are very different: seaweed grown attached to ropes in the sea and exported as low priced raw material, and a shellfish grown in land based systems and exported as a high priced food. Both of them provide income and employment, but not food for Africans. </p>
<p>There have been numerous attempts to grow marine fish and prawns in South Africa <a href="https://www.brandsouthafrica.com/investments-immigration/science-technology/the-growth-of-fish-farming-in-south-africa">in land-based systems</a>. This works for abalone – does it often fail for fish because of a lower-priced product? Successful operations elsewhere involving sea-cage production of fish such as salmon operate as simpler systems, without <a href="https://www.dyrevern.no/english/fish-farming-in-norway">large-scale water pumping</a>. </p>
<p>South Africa has particular constraints for marine aquaculture having a very straight coastline with high wave energy, mostly unsuitable for rafts and cages. Most of South Africa’s offshore marine aquaculture happens in Saldanha Bay on the west coast, with plans to <a href="http://www.slrconsulting.com/media/files/site/DAFF-Saldanha-ADZ.pdf">extend the area used</a>, and there are a limited number of other feasible sites.</p><img src="https://counter.theconversation.com/content/78861/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Bolton receives funding from the National Research Foundation (South Africa).</span></em></p>In light of World Oceans Day, it’s important to note the important role aquaculture can have on the continent.John Bolton, Professor of Biology and a marine plant biologist, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/729332017-03-20T01:32:29Z2017-03-20T01:32:29ZWant to eat fish that’s truly good for you? Here are some guidelines to reeling one in<figure><img src="https://images.theconversation.com/files/159698/original/image-20170307-20759-18dc9ix.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tuna being lifted from a fishing boat.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fishing-boat-unloading-tuna-harbor-pier-361749704">From www.shutterstock.com</a></span></figcaption></figure><p>Seafood is very healthy to eat – all things considered. Fish and shellfish are an important source of protein, vitamins and minerals, and they are low in saturated fat. But seafood’s claim to fame is its omega-3 fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), all of which are beneficial to health. The <a href="https://health.gov/dietaryguidelines/2015/guidelines/chapter-1/a-closer-look-inside-healthy-eating-patterns/#callout-seafood">U.S. Dietary Guidelines for Americans strongly suggest</a> that adults eat two servings of seafood, or a total of eight ounces, per week. </p>
<p>Omega-3s are today’s darling of the nutrition world, and <a href="https://www.nap.edu/catalog/11762/seafood-choices-balancing-benefits-and-risks">many observational studies have indeed shown them to benefit a range of conditions</a> such as high blood pressure, stroke, certain cancers, asthma, Type 2 diabetes and Alzheimer’s disease. However, <a href="https://well.blogs.nytimes.com/2015/03/30/fish-oil-claims-not-supported-by-research/?_r=0">there isn’t complete scientific agreement on the health benefits</a> of omega-3s, especially when considering the lack of strong evidence from randomized clinical trials. </p>
<p>The strongest evidence exists for a cardiovascular health benefit, and from consuming seafood (not just fish oil), which is significant because heart disease is the <a href="https://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm">leading cause of death</a> in the U.S.</p>
<p>One of the things I research is Americans’ meat and protein consumption. Though many of us are concerned about getting enough protein, most <a href="https://www.cambridge.org/core/journals/public-health-nutrition/article/div-classtitlea-critical-examination-of-the-available-data-sources-for-estimating-meat-and-protein-consumption-in-the-usadiv/9AB1A6CB6246362203D15375899CABF3">Americans actually get more than enough protein</a> in their diets. Rather, the problem is that most of us don’t include enough <a href="https://www.cambridge.org/core/journals/public-health-nutrition/article/div-classtitlea-critical-examination-of-the-available-data-sources-for-estimating-meat-and-protein-consumption-in-the-usadiv/9AB1A6CB6246362203D15375899CABF3">variety of protein sources in our diet</a>. We eat a lot of poultry and red meat but not as much seafood, nuts, beans, peas, and seeds. For seafood in particular, consumption is estimated to be closer to <a href="https://www.ers.usda.gov/amber-waves/2016/october/americans-seafood-consumption-below-recommendations/">2.7 ounces of seafood per week per person</a>, well below the recommended eight ounces.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/157017/original/image-20170215-27402-16jzh7z.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Consumption from the Protein Foods Group heavily leans toward poultry and red meat, rather than seafood and plant-based sources.</span>
<span class="attribution"><span class="source">USDA Economic Research Service</span></span>
</figcaption>
</figure>
<p>So the solution might seem simple: Increase public health messaging along the lines of: “Seafood is healthy. Eat more of it.” But it’s a bit more complicated than that.</p>
<h2>Complication #1: Omega-3 fatty acids vary from fish to fish</h2>
<p>Here’s the catch: If you are dutifully eating your two servings a week, but it’s from tilapia, shrimp, scallops or catfish, you won’t actually be getting much of the health benefits from the omega-3 fatty acids.</p>
<p>That’s because <a href="https://www.ars.usda.gov/ARSUserFiles/80400525/Articles/Eb09_Fish.pdf">seafood varies in its omega-3 fatty acids content</a>, and many commonly consumed seafoods are not actually that high in omega-3s. </p>
<p>The top five seafood products consumed in the U.S. are shrimp, salmon, canned tuna, tilapia and Alaskan pollock (think fishsticks). Together, these seafood products total about <a href="https://www.ers.usda.gov/amber-waves/2016/october/americans-seafood-consumption-below-recommendations/">three-fourths of U.S. seafood consumption</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=492&fit=crop&dpr=1 600w, https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=492&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=492&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=618&fit=crop&dpr=1 754w, https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=618&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/157198/original/image-20170216-32722-relehw.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=618&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Most frequently consumed seafood in the U.S.</span>
<span class="attribution"><span class="source">USDA Economic Research Service</span></span>
</figcaption>
</figure>
<p>Let’s take a look at the omega-3s content of these top seafood choices. Salmon is a good choice here, even though the total of omega-3s <a href="http://link.springer.com/article/10.1007%2Fs11745-014-3932-5">varies considerably by type of salmon</a> (the species and whether it is farmed or wild-caught). Regardless of the type, salmon is still one of the best omega-3 sources. </p>
<p>Canned tuna is an okay source, but it’s a bit of mixed bag (white tuna has more omega-3s than light tuna).</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159699/original/image-20170307-20759-nzjdtl.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">Fish sticks are a popular choice but likely do not have a lot of omega-3s in them.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/303277838?src=SfhQrTsVlue2Hek_YS7ZZg-1-0&size=huge_jpg">From www.shutterstock.com</a></span>
</figcaption>
</figure>
<p>Meanwhile, the other top seafood products – shrimp, tilapia and Alaskan pollock – are all <a href="http://www.seafoodhealthfacts.org/seafood-nutrition/healthcare-professionals/omega-3-content-frequently-consumed-seafood-products">fairly low in omega-3s</a>.</p>
<p>In short, we’re not eating a lot of fish to begin with, and much of the fish we do eat is not actually that high in omega-3 fatty acids.</p>
<h2>Complication #2: Mercury</h2>
<p>A naturally occurring heavy metal in rock, mercury is <a href="https://www.epa.gov/mercury/basic-information-about-mercury">released into the environment</a> primarily through human processes, such as the burning of fossil fuels. </p>
<p>Mercury makes its way into our waterways and <a href="https://www.scientificamerican.com/article/how-does-mercury-get-into/">bioaccumulates</a> in the marine food chain. Generally speaking, small fish and shellfish are low in mercury, while the most mercury accumulates in big, long-lived, predator fish, such as king mackerel, marlin, orange roughy, shark, swordfish, ahi (or yellowfin) tuna and bigeye tuna. </p>
<p>Humans, of course, are also part of that food chain. When we eat those big, long-lived predator fish, we ingest the mercury that’s accumulated in them.</p>
<p><a href="https://www.epa.gov/mercury/basic-information-about-mercury">Consuming mercury is definitely not a good thing</a>. A little bit here and there is probably not going to harm the average adult, but with high exposure, mercury can damage key organs. Fetuses, infants and young children are vulnerable to mercury toxicity, as high exposure can cause serious, irreversible developmental and neurological damage.</p>
<p>To minimize mercury exposure in women and young children, the Environmental Protection Agency (EPA) and Federal Drug Administration (FDA) <a href="http://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm393070.htm">announced new mercury in seafood guidelines</a> on Jan. 18, 2017. There are three categories – Best Choices, Good Choices and Choices to Avoid, and while most types of seafood clearly fall in just one category, some classifications are species-specific. </p>
<p>Tuna shows up in all three categories: canned light tuna is a Best Choice, canned white tuna is a Good Choice, but watch out for Bigeye tuna - it’s a Choice to Avoid. </p>
<p>For optimizing the health benefits, the best seafood choices are those high in omega-3s and low in mercury. <a href="https://www.choosemyplate.gov">ChooseMyPlate</a> lists several seafood options that <a href="https://www.choosemyplate.gov/ten-tips-eat-seafood">fit nicely in both categories</a>, including salmon, trout, oysters, herring and sardines, and Atlantic and Pacific mackerel. </p>
<h2>Complication #3: Sustainability</h2>
<p>There is also the issue of sustainability. </p>
<p>Let’s again take the <a href="http://www.seafoodwatch.org/seafood-recommendations/groups/tuna">case of tuna</a>. For certain species, the method of harvest and the location of harvest matter a great deal. Here’s an example from the Monterey Bay Aquarium’s <a href="http://www.seafoodwatch.org">Seafood Watch</a> guide: If you purchase a can of light tuna that’s trawl-caught in the East Pacific – that’s a Best Choice. </p>
<p>But if that canned light tuna is caught with a deep-set long line in the Hawaii Western Central Pacific, now it’s a Good Alternative. And canned light tuna caught on a <a href="http://www.fao.org/fishery/fishtech/40/en">purse seine</a> in the Indian Ocean? Now we’re squarely in the Avoid category.</p>
<p>By now you are probably asking if there are any win-win-win fish. Yes! Alaskan salmon is a popular one, but Alaskan salmon is sold at a premium price. Most of the <a href="http://www.seafoodhealthfacts.org/seafood-choices/description-top-commercial-seafood-items/salmon">salmon sold </a>in the U.S. is farmed Atlantic salmon, which typically has a poor sustainability rating. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159700/original/image-20170307-20749-244aaq.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">U.S. farmed rainbow trout like this one can be good for dinner.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/rainbow-trout-oncorhynchus-mykiss-537243493?src=HP7joOY2HcbxPc-JNpSFjQ-1-5">From www.shutterstock.com</a></span>
</figcaption>
</figure>
<p>Pacific sardines, farmed mussels, farmed rainbow trout and Atlantic mackerel (not trawled) are some other “win-win-win” options.</p>
<h2>How can I make an informed decision?</h2>
<p>Making informed choices about seafood isn’t easy, and it is complicated by <a href="https://crisbits.org/2016/10/seafood-fraud-see-may-not-get/">seafood fraud</a>. But there are some resources to help.</p>
<p>Eco-certification labels can help you make a decision without doing all the research yourself. Not all eco-labels are created equal, though, so a good place to scope out what to look for is the <a href="https://www.seafoodwatch.org">Seafood Watch</a> website. There, you can find a list of eco-certification labels for specific seafood products that, at a minimum, meet yellow “Good Alternative” recommendations. </p>
<p>There are also a number of consumer seafood guides, and with a little upfront research, these can help you make purchasing decisions when you get to the grocery store or restaurant. Many guides use a <a href="http://www.bbc.com/news/health-37389804">traffic light system</a> to clearly designate choices with a green, yellow or red light signs. </p>
<p>Additionally, the new <a href="http://www.iuufishing.noaa.gov/RecommendationsandActions/RECOMMENDATION1415/FinalRuleTraceability.aspx">Seafood Import Monitoring Program</a>, a governmental program that goes into effect this year, will <a href="https://crisbits.org/2017/01/u-s-making-traceability-part-seafood-supply-chain/">help to combat the problem of seafood fraud</a>. But you should still always be vigilant for prices that seem too good to be true.</p>
<p>If your only concern is reducing mercury content, the EPA and FDA guide <a href="http://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm393070.htm">“Eating Fish: What Pregnant Women and Parents Should Know</a>” should suffice. For sustainability concerns, the Monterey Bay Aquarium’s <a href="https://www.seafoodwatch.org/seafood-recommendations">Seafood Watch</a> guide allows you to search for options using a traffic light system, or you can look for information by the type of seafood. If you’re looking for a fish that meets all three criteria, the Environmental Working Group’s <a href="http://www.ewg.org/research/ewgs-good-seafood-guide">Consumer Guide to Seafood</a> and the Environmental Defense Fund’s <a href="http://seafood.edf.org">Seafood Selector</a> both provide comprehensive information.</p>
<p>When making food choices, sometimes we’re fortunate and the health and sustainability goals line up. Eating less red and processed meat, for example, is a choice that’s <a href="http://pubmedcentralcanada.ca/pmcc/articles/PMC3712342/">good for your health</a> and <a href="http://www.pewtrusts.org/en/research-and-analysis/reports/2008/04/29/putting-meat-on-the-table-industrial-farm-animal-production-in-america">better for the environment</a>. Unfortunately, with many seafood choices, these three important considerations – omega-3s, mercury and sustainability – sometimes, but don’t often, align as we might like them to.</p><img src="https://counter.theconversation.com/content/72933/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Keri Szejda's position is funded by the Michigan State University's Center for Research on Ingredient Safety.</span></em></p>Recently revised guidelines on mercury in seafood suggest cutting bait on some fish but making sure you eat other types. Then there are omega-3s to consider. Here are some tips to help you choose.Keri Szejda, Postdoctoral Research Associate, Center for Research on Ingredient Safety, Arizona State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/720992017-02-13T14:45:07Z2017-02-13T14:45:07ZFinding ways to double tilapia production in Tanzania without doing damage<figure><img src="https://images.theconversation.com/files/156157/original/image-20170209-28743-lykw0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tanzania has around 30 species of tilapia, 11 of which are found nowhere else on earth. </span> <span class="attribution"><span class="source">Reuters/Antony Njuguna</span></span></figcaption></figure><p>Tanzania is rich in exciting wildlife that has helped make it a <a href="http://allafrica.com/stories/201609270012.html">thriving</a> tourist destination. But some of its less photogenic species could also play an important role in the country’s economic development.</p>
<p>In the beautiful setting of Zanzibar it’s easy to forget that around a third of Tanzanian children under five are stunted due to <a href="https://www.unicef.org/tanzania/nutrition.html">malnutrition</a>. One in ten women are also undernourished. They are more likely to give birth to underweight infants, perpetuating the impact of <a href="https://www.unicef.org/tanzania/nutrition.html">undernutrition</a> down the generations.</p>
<p>Population growth is increasing demand for animal protein. Fish and fisheries products can provide a valuable source of protein, as well as essential micronutrients for balanced nutrition and health. But domestic production is unable to keep pace. So imports are <a href="http://www.fao.org/ag/agn/nutrition/tza_en.stm">filling</a> the gap. Between 2010 and 2013 imports of fish and fishery products <a href="http://www.mifugouvuvi.go.tz/wp-content/uploads/2012/12/ANNUAL-STATISTICS-REPORT-2013.pdf">increased</a> by 240%.</p>
<p>Worldwide, aquaculture – the farming of plants, algae (for instance, seaweed), and animals in aquatic environments – grows faster than any other food-production sector. This is often referred to as a <a href="http://www.economist.com/node/1974450">blue revolution</a>. In Africa, the industry is growing by 11.7% every year. But 90% of that growth is in just two countries – Egypt and Nigeria. </p>
<p>In <a href="http://repository.udsm.ac.tz:8080/xmlui/handle/123456789/1418">Tanzania</a>, aquaculture is still largely a small-scale rural initiative. It is characterised by small pond culture and contributes only 1.4% to GDP. There is much greater potential.</p>
<p>Inland water covers <a href="http://tafiri.weebly.com/">about</a> 6.5% of the total land area, including the Great Lakes –- Lake Victoria, Tanganyika and Nyasa/Malawi. The lakes are recognised as one of only 25 <a href="http://www.cnrs.fr/inee/recherche/fichiers/Biodiversite_hotspots.pdf">biodiversity hotspots</a> in the world because they are home to hundreds of species of <a href="https://www.scientificamerican.com/article/the-extraordinary-evolution-of-cichlid-fishes/">cichlid fish</a>. These include around 30 species of tilapia, 11 of which are not found anywhere else on earth. </p>
<p>The Earlham Institute and Bangor University, as part of an international consortium of organisations, are working to characterise the genetics of tilapia species in Tanzania. The larger consortium includes the Earlham Institute, Bangor University, the Swedish University of Agricultural Sciences, <a href="http://www.worldfishcenter.org">WorldFish</a>, the University of Dar es Salaam, Sokoine University of Agriculture, and the Tanzanian Fisheries Research Institute. The aim is to improve aquaculture and fish production, while preserving Tanzania’s natural diversity and resources.</p>
<h2>Farming tilapia</h2>
<p>Tilapia are particularly suitable for aquaculture because they are able to tolerate different environments and conditions. Their growth rates are also relatively fast, and they have low system input <a href="http://blog.worldfishcenter.org/2015/11/tilapia-a-nutritous-environmentally-friendly-fish/">requirements</a>. They’re second only to carp as the world’s <a href="http://www.fao.org/3/a-i5555e.pdf">most frequently</a> farmed fish. </p>
<p>To help harness this potential, the consortium received funding from the Swedish “Agriculture for Food Security 2030” (AgriFoSe) and the Swedish University of Agricultural Sciences. The participation of scientists from Bangor University and Earlham Institute was supported by a BBSRC award from the <a href="http://www.bbsrc.ac.uk/funding/filter/global-challenges-research-fund/">Global Challenges Research Fund</a> to bring together Tanzanian scientists, fish farmers and government officers with experts from around the world. </p>
<p>Last year the consortium drew up a resolution to establish a National Aquaculture Development Centre in Tanzania. The centre could help triple the contribution that aquaculture makes to the economy, <a href="http://www.mof.go.tz/mofdocs/overarch/Vision2025.pdf">double the production</a> of fish in the country by 2025 and help improve access to fish as a protein source for those most vulnerable to undernutrition.</p>
<p>The <a href="http://www.mifugouvuvi.go.tz/">Ministry of Agriculture Livestock and Fisheries</a> welcomed the centre’s input on developing new policy briefs that could help make the goals a reality. </p>
<p>As one of the partners the <a href="http://www.earlham.ac.uk/preservation-wild-tilapia-genetic-resources-aquaculture">Earlham Institute</a>, in close collaboration with Bangor University, can provide access to some of the most advanced sequencing technology in the world and training in how to apply it. This technology allows for the rapid identification of tilapia species that are responsible for traits of commercial importance, such as good growth rate and efficient use of feed.</p>
<p>The insitute can help characterise the diversity of wild tilapia species found in the country’s lakes, rivers, dams and wetlands. This analysis helps to identify which species have valuable traits for developing new breeding stock. </p>
<p>By developing broodstock from native tilapia, Tanzania has the potential to develop an independent industry. This would be based on its own supply of fingerlings (young fish), rather than relying solely on non-native species. In the 1980s Oreochromis niloticus (Nile tilapia) and Lates niloticus (Nile perch) were introduced to boost fisheries in Lake Victoria. Indigenous tilapia species <a href="https://www.researchgate.net/publication/271123878_The_tilapiine_fish_stock_of_Lake_Victoria_before_and_after_the_Nile_perch_upsurge">declined</a> to extremely low levels or vanished from the lake altogether.</p>
<p>A Tanzanian aquaculture seed bank could be valuable for breeders worldwide, for example by offering strains adapted to harsh environments.</p>
<h2>New smartphone app</h2>
<p>With Bangor University and software development partners Geosho, we are also developing a new way to track invasive species. A new smartphone app, “<a href="http://bangoriaa.com/tilapia-mapping-application/">TilapiaMap</a>”, can be used to help identify tilapia species in the field and map the distribution of recorded species. It could help highlight regions rich in pure species, where conservation measures could be put in place. It could also flag regions with a high number of hybrids that pose a biosecurity risk.</p>
<p>In this way, we hope to help preserve the natural biodiversity on which an independent industry could be built. This could make a real contribution to food security and could continue to supply novel traits for breeding into the future.</p><img src="https://counter.theconversation.com/content/72099/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Federica Di Palma receives funding from BBSRC UK</span></em></p>Tilapia could play an important role in Tanzania’s economic development.Federica Di Palma, Director of Science, Earlham InstituteLicensed as Creative Commons – attribution, no derivatives.