tag:theconversation.com,2011:/us/topics/ponds-40756/articlesPonds – The Conversation2023-05-26T12:27:40Ztag:theconversation.com,2011:article/2058962023-05-26T12:27:40Z2023-05-26T12:27:40ZThe Supreme Court just shriveled federal protection for wetlands, leaving many of these valuable ecosystems at risk<figure><img src="https://images.theconversation.com/files/528434/original/file-20230525-17-782ull.jpg?ixlib=rb-1.1.0&rect=15%2C15%2C3409%2C2571&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Many ecologically important wetlands, like these in Kulm, N.D., lack surface connections to navigable waterways.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/kgatnj">USFWS Mountain-Prairie/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>The U.S. Supreme Court has ruled in <a href="https://supreme.justia.com/cases/federal/us/598/21-454/">Sackett v. EPA</a> that federal protection of wetlands encompasses only those wetlands that directly adjoin rivers, lakes and other bodies of water. This is an extremely narrow interpretation of the Clean Water Act that could expose many wetlands across the U.S. to filling and development.</p>
<p>Under this keystone environmental law, federal agencies take the lead in regulating water pollution, while state and local governments regulate land use. Wetlands are areas where <a href="https://www.epa.gov/wetlands/what-wetland">land is wet for all or part of the year</a>, so they straddle this division of authority.</p>
<p><a href="https://www.epa.gov/wetlands/classification-and-types-wetlands#undefined">Swamps, bogs, marshes and other wetlands</a> provide valuable ecological services, such as filtering pollutants and soaking up floodwaters. Landowners must obtain permits to discharge <a href="https://www.fedcenter.gov/assistance/facilitytour/construction/dredging/">dredged or fill material</a>, such as dirt, sand or rock, in a protected wetland. </p>
<p>This can be time-consuming and expensive, which is why the Supreme Court’s ruling on May 25, 2023, will be of keen interest to developers, farmers and ranchers, along with conservationists and the agencies that administer the Clean Water Act – namely, the Environmental Protection Agency and the U.S. Army Corps of Engineers. </p>
<p>For the last 45 years – and under eight different presidential administrations – the EPA and the Corps have required discharge permits in wetlands “adjacent” to water bodies, even if a dune, levee or other barrier separated the two. The Sackett decision upends that approach, <a href="https://www.everycrsreport.com/files/20160427_RL33263_e0b1d527d85d13721eb7f29d3e1446c517900c45.pdf">leaving tens of millions of acres of wetlands at risk</a>. </p>
<figure>
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<figcaption><span class="caption">The U.S. has lost more than half of its original wetlands, mainly due to development and pollution.</span></figcaption>
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<h2>The Sackett case</h2>
<p>Idaho residents Chantell and Mike Sackett own a parcel of land located 300 feet from Priest Lake, <a href="https://www.eenews.net/articles/idaho-couple-returns-to-supreme-court-to-wage-new-wotus-war/">one of the state’s largest lakes</a>. The parcel once was part of a large wetland complex. Today, even after <a href="https://www.spokesman.com/stories/2011/nov/06/private-land-public-battle/">the Sacketts cleared the lot</a>, it still has some wetland characteristics, such as saturation and ponding in areas where soil was removed. Indeed, it is still hydrologically connected to the lake and neighboring wetlands by water that flows at a shallow depth underground. </p>
<p>In preparation to build a house, the Sacketts had fill material placed on the site without obtaining a Clean Water Act permit. The EPA issued an order in 2007 stating that the land contained wetlands subject to the law and requiring the Sacketts to restore the site. The Sacketts sued, <a href="https://www.spokesman.com/stories/2011/nov/06/private-land-public-battle/">arguing that their property was not a wetland</a>. </p>
<p>In 2012, the Supreme Court held that the Sacketts had the right to challenge EPA’s order and <a href="https://www.supremecourt.gov/opinions/11pdf/10-1062.pdf">sent the case back to the lower courts</a>. After <a href="https://cdn.ca9.uscourts.gov/datastore/opinions/2021/08/16/19-35469.pdf">losing below on the merits</a>, they returned to the Supreme Court with a suit asserting that their property was not federally protected. This claim in turn raised a broader question: What is the scope of federal regulatory authority under the Clean Water Act?</p>
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<a href="https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Homes line the edges of a river." src="https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528437/original/file-20230525-22692-3hhbom.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">Housing encroaches on Caloosahatchee River wetlands in Fort Myers, Fla.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/fort-myers-florida-palm-acres-housing-development-news-photo/1428541733">Jeffrey Greenberg/Universal Images Group via Getty Images</a></span>
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<h2>What are ‘waters of the United States’?</h2>
<p>The Clean Water Act regulates <a href="https://www.govinfo.gov/content/pkg/USCODE-2020-title33/pdf/USCODE-2020-title33-chap26-subchapIII-sec1311.pdf">discharges of pollutants</a> into “<a href="https://www.epa.gov/wotus/about-waters-united-states">waters of the United States</a>.” Lawful discharges may occur if a pollution source obtains a permit under either <a href="https://www.govinfo.gov/content/pkg/USCODE-2011-title33/pdf/USCODE-2011-title33-chap26-subchapIV-sec1344.pdf">Section 404 of the act</a> for dredged or fill material, or <a href="https://www.govinfo.gov/content/pkg/USCODE-1994-title33/pdf/USCODE-1994-title33-chap25-subchapIV-sec1342.pdf">Section 402</a> for other pollutants. </p>
<p>The Supreme Court has previously recognized that the “waters of the United States” include not only navigable rivers and lakes, but also wetlands and waterways that are connected to navigable bodies of water. But many wetlands are not wet year-round, or are not connected at the surface to larger water systems. Still, they can have <a href="https://theconversation.com/small-streams-and-wetlands-are-key-parts-of-river-networks-heres-why-they-need-protection-110342">important ecological connections</a> to larger water bodies.</p>
<p>In 2006, when the court last took up this issue, no majority was able to agree on how to define “waters of the United States.” Writing for a plurality of four justices in U.S. v. Rapanos, Justice Antonin Scalia <a href="https://www.oyez.org/cases/2005/04-1034">defined the term narrowly</a> to include only relatively permanent, standing or continuously flowing bodies of water such as streams, oceans, rivers and lakes. Waters of the U.S., he contended, should not include “ordinarily dry channels through which water occasionally or intermittently flows.” </p>
<p>Acknowledging that wetlands present a tricky line-drawing problem, Scalia proposed that the Clean Water Act should reach “only those wetlands with a continuous surface connection to bodies that are waters of the United States in their own right.” </p>
<p>In a concurring opinion, Justice Anthony Kennedy took a very different approach. “Waters of the U.S.,” he wrote, should be interpreted in light of the Clean Water Act’s objective of “restoring and maintaining the chemical, physical, and biological integrity of the Nation’s waters.” </p>
<p>Accordingly, Kennedy argued, the Clean Water Act should cover wetlands that have a “significant nexus” with navigable waters – “if the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’” </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CsmaAv2LpR6/?utm_source=ig_web_copy_link\u0026igshid=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Neither Scalia’s nor Kennedy’s opinion attracted a majority, so lower courts were left to sort out which approach to follow. Most applied Kennedy’s significant nexus standard, while a few held that the Clean Water Act applies if <a href="https://crsreports.congress.gov/product/pdf/R/R46927">either Kennedy’s standard or Scalia’s is satisfied</a>.</p>
<p>Regulators have also struggled with this question. The Obama administration incorporated Kennedy’s “significant nexus” approach into a <a href="https://www.govinfo.gov/content/pkg/FR-2015-06-29/pdf/2015-13435.pdf">2015 rule</a> that followed an extensive rulemaking process and a <a href="https://theconversation.com/epas-clean-water-rule-whats-at-stake-and-what-comes-next-42466">comprehensive peer-reviewed scientific assessment</a>. The Trump administration then replaced the 2015 rule with <a href="https://www.govinfo.gov/content/pkg/FR-2020-04-21/pdf/2020-02500.pdf">a rule of its own</a> that <a href="https://theconversation.com/repealing-the-clean-water-rule-will-swamp-the-trump-administration-in-wetland-litigation-123565">largely adopted the Scalia approach</a>. </p>
<p>The Biden administration <a href="https://www.epa.gov/wotus">responded with its own rule</a> defining waters of the United States in terms of the presence of either a significant nexus or continuous surface connection. However, this rule was <a href="https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update">promptly embroiled in litigation</a> and will require reconsideration in light of Sackett v. EPA.</p>
<h2>The Sackett decision and its ramifications</h2>
<p>The Sackett decision adopts Scalia’s approach from the 2006 Rapanos case. Writing for a five-justice majority, Justice Samuel Alito declared that “waters of the United States” includes only relatively permanent, standing or continuously flowing bodies of water, such as streams, oceans, rivers, lakes – and wetlands that have a continuous surface connection with and are indistinguishably part of such water bodies. </p>
<p>None of the nine justices adopted Kennedy’s 2006 “significant nexus” standard. However, Justice Brett Kavanaugh and the three liberal justices disagreed with the majority’s “continuous surface connection” test. That test, Kavanaugh <a href="https://supreme.justia.com/cases/federal/us/598/21-454/">wrote in a concurrence</a>, is inconsistent with the text of the Clean Water Act, which extends coverage to “adjacent” wetlands – including those that are near or close to larger water bodies. </p>
<p>“Natural barriers such as berms and dunes do not block all water flow and are in fact evidence of a regular connection between a water and a wetland,” Kavanaugh explained. “By narrowing the Act’s coverage of wetlands to only adjoining wetlands, the Court’s new test will leave some long-regulated adjacent wetlands no longer covered by the Clean Water Act, with significant repercussions for water quality and flood control throughout the United States.” </p>
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<p>The majority’s ruling leaves little room for the EPA or the Army Corps of Engineers to issue new regulations that could protect wetlands more broadly. </p>
<p>The court’s requirement of a continuous surface connection means that federal protection may no longer apply to many areas that critically affect the water quality of U.S. rivers, lakes and oceans – including seasonal streams and wetlands that are near or intermittently connected to larger water bodies. It might also mean that construction of a road, levee or other barrier separating a wetland from other nearby waters could remove an area from federal protection. </p>
<p>Congress could amend the Clean Water Act to expressly provide that “waters of the United States” includes wetlands that the court has now stripped of federal protection. However, <a href="https://sgp.fas.org/crs/misc/R43943.pdf">past efforts to legislate a definition have fizzled</a>, and today’s closely divided Congress is unlikely to fare any better.</p>
<p>Whether states will fill the breach is questionable. Many states have not adopted regulatory protections for waters that are <a href="https://www.eli.org/sites/default/files/files-pdf/52.10679.pdf">outside the scope of “waters of the United States</a>.” In many instances, new legislation – and perhaps entirely new regulatory programs – will be needed. </p>
<p>Finally, a concurring opinion by Justice Clarence Thomas hints at potential future targets for the court’s conservative supermajority. Joined by Justice Neil Gorsuch, Thomas suggested that the Clean Water Act, as well as other federal environmental statutes, lies beyond Congress’ authority to regulate activities that affect interstate commerce, and could be vulnerable to constitutional challenges. In my view, Sackett v. EPA might be just one step toward the teardown of federal environmental law. </p>
<p><em>This is an update of an <a href="https://theconversation.com/which-wetlands-should-receive-federal-protection-the-supreme-court-revisits-a-question-it-has-struggled-in-the-past-to-answer-185282">article</a> originally published on Sept. 26, 2022.</em></p><img src="https://counter.theconversation.com/content/205896/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Albert C. Lin was a trial attorney for the Environment and Natural Resources Division of the U.S. Department of Justice from 1998 to 2003. He served as a law clerk to the Honorable Merrick Garland of the U.S. Court of Appeals for the D.C. Circuit and to the Honorable James Browning of the U.S. Court of Appeals for the Ninth Circuit.</span></em></p>In Sackett v. EPA, a suit filed by two homeowners who filled in wetlands on their property, the Supreme Court has drastically narrowed the definition of which wetlands qualify for federal protection.Albert C. Lin, Professor of Law, University of California, DavisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1993622023-02-09T16:18:08Z2023-02-09T16:18:08ZEarth has lost one-fifth of its wetlands since 1700 – but most could still be saved<figure><img src="https://images.theconversation.com/files/509148/original/file-20230209-28-572jb3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4454%2C2967&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A capybara in the Iberá Wetlands (Esteros del Iberá) of northeast Argentina.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/capybara-sticks-head-plantcovered-waters-ibera-1189374100">Kylie Nicholson/Shutterstock</a></span></figcaption></figure><p>Like so many of the planet’s natural habitats, wetlands have been systematically destroyed over the past 300 years. Bogs, fens, marshes and swamps have disappeared from maps and memory, having been drained, dug up and built on. </p>
<p>Being close to a reliable source of water and generally flat, wetlands were always prime targets for building towns and farms. Draining their waterlogged soils has produced some of the most fertile farmland available. </p>
<p>But wetlands also offer some of the best natural solutions to modern crises. They can clean water by removing and filtering pollutants, displace floodwater, shelter wildlife, improve our mental and physical wellbeing and capture climate-changing amounts of carbon. </p>
<p>Peatlands, a particular type of wetland, store <a href="https://www.unep.org/news-and-stories/story/peatlands-store-twice-much-carbon-all-worlds-forests">at least twice</a> the carbon of all the world’s forests.</p>
<p>How much of the Earth’s precious wetlands have been lost since 1700 was recently addressed by <a href="https://www.nature.com/articles/s41586-022-05572-6">a major new study</a> published in Nature. Previously, it was feared that <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev.energy.30.050504.144248">as much as 50%</a> of our wetlands might have been wiped out. However, the latest research suggests that the figure is actually closer to 21% - an area the size of India. </p>
<p>Some countries have seen much higher losses, with Ireland losing more than 90% of its wetlands. The main reason for these global losses has been the drainage of wetlands for growing crops.</p>
<figure class="align-center ">
<img alt="A waterlogged wilderness with tufts of vegetation growing amid the water." src="https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509159/original/file-20230209-18-ehsihr.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">A wetland is, like this peat bog, a terrestrial habitat where water is held on the land.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/peat-bog-national-park-sumava-europe-357530972">Kuttelvaserova Stuchelova/Shutterstock</a></span>
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<h2>Wetlands are not wastelands</h2>
<p>This is the most thorough investigation of its kind. The researchers used historical records and the latest maps to monitor land use on a global scale.</p>
<p>Despite this, the new paper highlights some of the scientific and cultural barriers to studying and managing wetlands. For instance, even identifying what is and isn’t a wetland is harder than for other habitats. </p>
<p>The defining characteristic of a wetland – being wet – is not always easily identified in each region and season. How much is the right amount of wetness? Some classification systems list <a href="https://www.ramsar.org/sites/default/files/documents/library/info2007-01-e.pdf">coral reefs</a> as wetlands, while others argue this is too wet. </p>
<p>And for centuries, wetlands were seen as unproductive wastelands ripe for converting to cropland. This makes records of where these ecosystems used to be sketchy at best.</p>
<p>The report shows clearly that the removal of wetlands is not spread evenly around the globe. Some regions have lost more than average. Around half of the wetlands in Europe have gone, with the UK losing 75% of its original area. </p>
<p>The US, central Asia, India, China, Japan and south-east Asia are also reported to have lost 50% of their original wetlands. It is these regional differences which promoted the idea that half of all the world’s wetlands had disappeared.</p>
<figure class="align-center ">
<img alt="Farmers bend over to extract rice from a paddy field." src="https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509153/original/file-20230209-28-wy0hh3.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">Farming has driven the destruction of wetlands globally.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/farmer-working-plant-rice-farm-thailand-460809358">Tridsanu Thopet/Shutterstock</a></span>
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</figure>
<p>This disparity is somewhat hopeful, as it suggests there are still plenty of wetlands which haven’t been destroyed – particularly the vast northern peatlands of Siberia and Canada.</p>
<h2>An ecological tonic</h2>
<p>Losing a wetland a few acres in size may not sound much on a global or even national scale, but it’s very serious for the nearby town that now floods when it rains and is catastrophic for the specialised animals and plants, like curlews and swallowtail butterflies, living there.</p>
<figure class="align-center ">
<img alt="A herd of flamingoes in a lagoon with a city skyline in the distance." src="https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509162/original/file-20230209-27-y5g44x.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">Wetlands offer food and habitat for a diverse range of species.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/thousands-greater-flamingos-phoenicopterus-roseus-ras-1922566502">Aleksandra Tokarz/Shutterstock</a></span>
</figcaption>
</figure>
<p>Fortunately, countries and international organisations are beginning to understand how important wetlands are locally and globally, with some adopting “no-net-loss” policies that oblige developers to restore any habitats they destroy. The UK has promised to <a href="https://www.gov.uk/government/news/sale-of-horticultural-peat-to-be-banned-in-move-to-protect-englands-precious-peatlands#:%7E:text=All%20sales%20of%20peat%20to,in%20a%20near%2Dnatural%20state.">ban the sale</a> of peat-based composts for amateur growers by 2024. </p>
<p>Wetland habitats are being conserved around the world, often at huge expense. Over US$10 billion (£8.2 billion) has been spent on a 35-year plan to restore the <a href="https://crsreports.congress.gov/product/pdf/IF/IF11336">Florida Everglades</a>, a unique network of subtropical wetlands, making it the largest and most expensive ecological restoration project in the world. </p>
<p>The creation of new wetlands is also underway in many places. The reintroduction of beavers to enclosures across Britain is expected to increase the nation’s wetland coverage, bringing with it all the advantages of these habitats. </p>
<p>Beaver dams and the wetlands they create reduce the <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/hyp.14017">effects of flooding</a> by up to 60% and can boost the area’s wildlife. One study showed the number of local <a href="https://www.sciencedirect.com/science/article/pii/S2351989419302732">mammal species</a> shot up by 86% thanks to these furry engineers. </p>
<figure class="align-center ">
<img alt="An aerial view of a coastal wetland." src="https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509150/original/file-20230209-24-wy0hh3.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">
<figcaption>
<span class="caption">Wetlands hold and slowly release water, helping to ease flooding and stall drought.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-view-lush-coastal-wetlands-uk-1489113977">Steved_np3/Shutterstock</a></span>
</figcaption>
</figure>
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Read more:
<a href="https://theconversation.com/beavers-and-oysters-are-helping-restore-lost-ecosystems-with-their-engineering-skills-podcast-198573">Beavers and oysters are helping restore lost ecosystems with their engineering skills – podcast</a>
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<p>Even the sustainable drainage system ponds developers create on the fringes of new housing estates could see pocket wetlands appearing in towns and cities across the UK. By mimicking natural drainage regimes instead of removing surface water with pipes and sewers, sustainable drainage systems can create areas of plants and water that have been shown to increase biodiversity, especially <a href="https://www.sciencedirect.com/science/article/pii/S0169204611000648">invertebrates</a>.</p>
<p>Whether the total global loss of wetlands is 20% or 50% doesn’t really matter. What does matter is that people stop looking at wetlands as wastelands, there for us to drain and turn into “useful” land. </p>
<p>As the UN recently pointed out, an <a href="https://unfccc.int/news/wetlands-disappearing-three-times-faster-than-forests">estimated 40%</a> of Earth’s species live and breed in wetlands and a billion people depend on them for their livelihoods. Conserving and restoring these vital habitats is key to achieving a sustainable future.</p>
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<figure class="align-right ">
<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><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
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<p class="fine-print"><em><span>Christian Dunn 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>The swamp has not yet been drained everywhere.Christian Dunn, Senior Lecturer in Natural Sciences, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1955022022-12-16T11:50:47Z2022-12-16T11:50:47ZHow wildlife in ponds has evolved to survive frozen water – and how you can help more animals stay alive<figure><img src="https://images.theconversation.com/files/499756/original/file-20221208-13-zix3b9.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1920%2C1281&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">"Great!"</span> <span class="attribution"><a class="source" href="https://pixabay.com/photos/duck-water-bird-water-fowl-animal-3944495/">Mabel Amber/Pixabay</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>When filled with ice-skaters or a clumsy Bambi on a Christmas card, a frozen pond is a merry sight. But spare a thought for the living things trapped below. The aerial wizardry of dragonflies and summer sculling of pond skaters are long gone. As the cold grips and shadows lengthen over the pond, its inhabitants face a terrible enemy: ice.</p>
<p>But while the cold of winter is a threat to most wildlife, it can be endured. Many land-based creatures – particularly amphibians such as toads and newts, and other animals without spines known as invertebrates – have evolved the ability to cool their bodily fluids down to below zero. This allows them to sit out the lean months of winter without freezing.</p>
<p>For example, the wood frog can cope with up to <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/jez.2306">70%</a> of the water inside its body turning to ice. These frogs don’t lurk, iced up, in ponds, however – they nestle in the dry leaf litter of the woodland floor. They only head to ponds once they have thawed out in springtime, warmed up and ready for some frenzied reproduction.</p>
<p>During winter, the biggest danger for the pond life that becomes trapped in ice is internal freezing, as expanding ice wreaks havoc on cells and tissues.</p>
<h2>Winterkill is coming</h2>
<p>Hibernating pond invertebrates such as beetles, dragonfly larvae and waterboatmen (a type of aquatic bug) get around this problem by allowing internal fluids to freeze. Proteins in their blood encourage the formation of ice crystals which draw water out of vulnerable tissue. These little creatures are not only frozen but dried out – and all <a href="https://jlimnol.it/index.php/jlimnol/article/view/jlimnol.2004.s1.45">the safer for it</a>.</p>
<p>Other bugs rely on natural antifreeze chemicals in their fluids to resist freezing at temperatures <a href="https://core.ac.uk/download/pdf/235277932.pdf">well below 0°C</a>. Researchers tested several species of pond and stream beetle, mayfly and mollusc and found all of them could cool their internal temperature in water to between -3 and -7°C. However, if the ice ensnared them, even at higher temperatures, they were doomed. </p>
<figure class="align-center ">
<img alt="An oval-shaped beetle with feathery limbs." src="https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499759/original/file-20221208-6401-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Hardy beetles have evolved chemical defences against the chill.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/diving-beetle-pond-closeup-1334686157">Vitalii Hulai/Shutterstock</a></span>
</figcaption>
</figure>
<p>Some pond invertebrates prepare for winter by secreting insulating cocoons. The majority try to find refuge in deeper water or another pond, although some <a href="https://en.wikipedia.org/wiki/Prairie_Pothole_Region">Prairie Pothole</a> water boatmen huddle together in <a href="https://usurj.journals.usask.ca/article/view/38">icebound clusters</a>. This mass of dark little bodies may thaw out faster in the springtime sunshine, but not all will make it through alive.</p>
<p>Many species succumb, and scientists call these mass deaths in iced-over ponds “winterkill”. At least <a href="https://digitalcommons.denison.edu/facultypubs/163/">one study</a> has showed that numbers of invertebrates, tadpoles and fish can take years to recover from such a freeze. However, winterkill may also bring smaller inhabitants of ponds some longer-term benefits.</p>
<p>The word “winterkill” comes from fisheries, where the effect of prolonged ice cover and reduced oxygen – as gases dissolve less effectively and oxygen from plants is limited as they too die back – has long been known to <a href="https://esajournals.onlinelibrary.wiley.com/doi/abs/10.2307/1948427">kill lots of fish</a>. </p>
<p><a href="https://www.journals.uchicago.edu/doi/10.1899/0887-3593(2004)023%3C0237:WCIEOA%3E2.0.CO;2">A fortuitous experiment</a> on four frozen Albertan lakes, which were monitored for five years, showed the ecological consequences of winterkill clearly.</p>
<p>In two of the lakes, it did away with most of the fish – yet the other two, which were comparable in other ways, were unaffected. Invertebrate numbers shot up in the lakes where the fish died, with freshwater shrimps, caddisflies and midges particularly benefiting, but not in the other two.</p>
<p>Winterkill is a great example of how disturbances reset the ecological stage with a new cast of characters, creating richness and variety across the landscape.</p>
<h2>What to do if you have a pond</h2>
<p>What should you do if you have a pond (or more than one – a cluster is usually best for maximising the diversity of invertebrates and plants) that freezes? Reams of blogs and leaflets offer <a href="https://freshwaterhabitats.org.uk/habitats/pond/cold-weather/">advice</a> on this topic.</p>
<figure class="align-center ">
<img alt="Water lilies encased in ice." src="https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499757/original/file-20221208-6292-p3m533.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">Pond plants take a long nap when ice sets in too.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/leaf-lily-frozen-pond-529066717">Kuiper/Shutterstock</a></span>
</figcaption>
</figure>
<p>Sweeping the snow off a pond and keeping some of its surface ice-free may well help aquatic life by letting in sunlight. But never smash a hole in the ice, since it might shock the fish to death. Indeed, when I last saw this attempted, the friend doing the smashing slipped over and landed in a sodden heap, so he was quite shocked too. Icy ponds are dangerous places so doing anything that risks you falling in is definitely best avoided.</p>
<p>Of course, our wildlife has been living with winterkills for thousands of years. Much better to make sure the whole landscape is rich in all sorts of ponds – shallow, deep, large, small, temporary or freezing – and then the frogs and bugs will do just fine on their own.</p><img src="https://counter.theconversation.com/content/195502/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mike Jeffries 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>Some species beat the big freeze with natural antifreeze in their blood.Mike Jeffries, Associate Professor, Ecology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1852822022-09-26T12:30:44Z2022-09-26T12:30:44ZWhich wetlands should receive federal protection? The Supreme Court revisits a question it has struggled in the past to answer<figure><img src="https://images.theconversation.com/files/484969/original/file-20220915-42480-6nr6ho.jpg?ixlib=rb-1.1.0&rect=44%2C0%2C4991%2C3309&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Wetlands like this one in California's Morro Bay Estuary shelter fish, animals and plants and help control flooding.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/wetlands-in-morro-bay-estuary-san-luis-obispo-county-news-photo/1379449063">Citizen of the Planet/UCG/Universal Images Group via Getty Images</a></span></figcaption></figure><p>The U.S. Supreme Court opens its new session on Oct. 3, 2022, with a high-profile case that could fundamentally alter the federal government’s ability to address water pollution. <a href="https://www.oyez.org/cases/2022/21-454">Sackett v. EPA</a> turns on a question that courts and regulators have struggled to answer for several decades: Which wetlands and bodies of water can the federal government regulate under the 1972 Clean Water Act?</p>
<p>Under this keystone environmental law, federal agencies take the lead in regulating water pollution, while state and local governments regulate land use. Wetlands are areas where <a href="https://www.epa.gov/wetlands/what-wetland">land is wet for all or part of the year</a>, so they straddle this division of authority.</p>
<p><a href="https://www.epa.gov/wetlands/classification-and-types-wetlands#undefined">Swamps, bogs, marshes and other wetlands</a> provide valuable ecological services, such as filtering pollutants and soaking up floodwaters. Landowners must obtain permits to discharge <a href="https://www.fedcenter.gov/assistance/facilitytour/construction/dredging/">dredged or fill material</a>, such as dirt, sand or rock, in a protected wetland. This can be time-consuming and expensive, which is why the case is of keen interest to developers, farmers and ranchers, along with conservationists and the agencies that administer the Clean Water Act – the Environmental Protection Agency and the U.S. Army Corps of Engineers. </p>
<p>The Supreme Court has already shown a willingness to <a href="https://theconversation.com/the-supreme-court-has-curtailed-epas-power-to-regulate-carbon-pollution-and-sent-a-warning-to-other-regulators-185281">curb federal regulatory power on environmental issues</a>. From my work as an <a href="https://scholar.google.com/citations?hl=en&user=njpqfiQAAAAJ">environmental law scholar</a>, I expect the court’s decision in this case to cut back on the types of wetlands that qualify for federal protection.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bFGMoFIjKRM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The U.S. has already lost more than half of its original wetlands, mainly because of development and pollution.</span></figcaption>
</figure>
<h2>The Sackett case</h2>
<p>Idaho residents Chantell and Mike Sackett own a parcel of land located 300 feet from Priest Lake, <a href="https://www.eenews.net/articles/idaho-couple-returns-to-supreme-court-to-wage-new-wotus-war/">one of the state’s largest lakes</a>. The parcel once was part of a large wetland complex. Today, even after <a href="https://www.spokesman.com/stories/2011/nov/06/private-land-public-battle/">the Sacketts cleared the lot</a>, it still has some wetland characteristics, such as saturation and ponding in areas where soil was removed. Indeed, it is still hydrologically connected to the lake and neighboring wetlands by water that flows at a shallow depth underground. </p>
<p>In preparation to build a house, the Sacketts had fill material placed on the site without obtaining a Clean Water Act permit. The EPA issued an order in 2007 stating that the land contained wetlands subject to the law and requiring the Sacketts to restore the site. The Sacketts sued, <a href="https://www.spokesman.com/stories/2011/nov/06/private-land-public-battle/">arguing that their property was not a wetland</a>. </p>
<p>In 2012, the Supreme Court held that the Sacketts had the right to challenge EPA’s order and <a href="https://www.supremecourt.gov/opinions/11pdf/10-1062.pdf">sent the case back to the lower courts</a>. Now, after <a href="https://cdn.ca9.uscourts.gov/datastore/opinions/2021/08/16/19-35469.pdf">losing below on the merits</a>, they are back before the Supreme Court. The current issue is whether the Sacketts’ property is federally protected, which in turn raises a broader question: What is the scope of federal regulatory authority under the Clean Water Act?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing how far U.S. Army Corps of Engineers jurisdiction over wetlands extends" src="https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=323&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=323&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=323&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=406&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=406&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485109/original/file-20220916-1035-g64i76.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=406&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 graphic shows the U.S. Army Corps of Engineers’ jurisdiction over discharging dredged or fill material into wetlands under Section 404 of the Clean Water Act. Coverage of isolated wetlands without a surface connection to rivers, lakes or harbors is less clear.</span>
<span class="attribution"><a class="source" href="https://www.spn.usace.army.mil/Portals/68/docs/regulatory/Jurisdictional%20Determinations/Jurisdictional-10-404-103.gif">USACE</a></span>
</figcaption>
</figure>
<h2>What are ‘waters of the United States’?</h2>
<p>The Clean Water Act regulates <a href="https://www.govinfo.gov/content/pkg/USCODE-2020-title33/pdf/USCODE-2020-title33-chap26-subchapIII-sec1311.pdf">discharges of pollutants</a> into “<a href="https://www.epa.gov/wotus/about-waters-united-states">waters of the United States</a>.” Lawful discharges may occur if a pollution source obtains a permit under either <a href="https://www.govinfo.gov/content/pkg/USCODE-2011-title33/pdf/USCODE-2011-title33-chap26-subchapIV-sec1344.pdf">Section 404 of the Act</a> for dredged or fill material, or <a href="https://www.govinfo.gov/content/pkg/USCODE-1994-title33/pdf/USCODE-1994-title33-chap25-subchapIV-sec1342.pdf">Section 402</a> for other pollutants. </p>
<p>The Supreme Court has previously recognized that the “waters of the United States” include not only navigable rivers and lakes, but also wetlands and waterways that are connected to navigable bodies of water. However, many wetlands are not wet year-round, or are not connected at the surface to larger water systems, but can still have <a href="https://theconversation.com/small-streams-and-wetlands-are-key-parts-of-river-networks-heres-why-they-need-protection-110342">important ecological connections</a> to larger water bodies.</p>
<p>In 2006, when the court last took up this issue, no majority was able to agree on how to define “waters of the United States.” Writing for a plurality of four justices in U.S. v. Rapanos, Justice Antonin Scalia <a href="https://www.oyez.org/cases/2005/04-1034">defined the term narrowly</a> to include only relatively permanent, standing or continuously flowing bodies of water such as streams, oceans, rivers and lakes. Waters of the U.S., he contended, should not include “ordinarily dry channels through which water occasionally or intermittently flows.” </p>
<p>Acknowledging that wetlands present a tricky line-drawing problem, Scalia proposed that the Clean Water Act should reach “only those wetlands with a continuous surface connection to bodies that are waters of the United States in their own right.” </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CWme74_D1eM/?utm_source=ig_web_copy_link","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>In a concurring opinion, Justice Anthony Kennedy took a very different approach. “Waters of the U.S.,” he wrote, should be interpreted in light of the Clean Water Act’s objective of “restoring and maintaining the chemical, physical, and biological integrity of the Nation’s waters.” </p>
<p>Accordingly, Kennedy argued, the Clean Water Act should cover wetlands that have a “significant nexus” with navigable waters – “if the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’” </p>
<p>Neither Scalia’s nor Kennedy’s opinion attracted a majority, so lower courts have been left to sort out which approach to follow. Most have applied Kennedy’s significant nexus standard, while a few have held that the Clean Water Act applies if <a href="https://crsreports.congress.gov/product/pdf/R/R46927">either Kennedy’s standard or Scalia’s is satisfied</a>.</p>
<p>Regulators have also struggled with this question. The Obama administration incorporated Kennedy’s “significant nexus” approach into a <a href="https://www.govinfo.gov/content/pkg/FR-2015-06-29/pdf/2015-13435.pdf">2015 rule</a> that followed an extensive rulemaking process and a <a href="https://theconversation.com/epas-clean-water-rule-whats-at-stake-and-what-comes-next-42466">comprehensive peer-reviewed scientific assessment</a>. The Trump administration then replaced the 2015 rule with <a href="https://www.govinfo.gov/content/pkg/FR-2020-04-21/pdf/2020-02500.pdf">a rule of its own</a> that <a href="https://theconversation.com/repealing-the-clean-water-rule-will-swamp-the-trump-administration-in-wetland-litigation-123565">largely adopted the Scalia approach</a>. The Biden administration has <a href="https://www.govinfo.gov/content/pkg/FR-2021-12-07/pdf/2021-25601.pdf">proposed a new rule</a> that would deem waters of the United States present if either a significant nexus or continuous surface connection is present. </p>
<h2>What’s at stake</h2>
<p>The court’s ultimate ruling in Sackett could offer lower courts, regulatory agencies and landowners clear direction on the meaning of “waters of the United States.” And it will likely affect the government’s ability to protect the nation’s waters. </p>
<p>A broad interpretation could include many <a href="https://theconversation.com/why-farmers-and-ranchers-think-the-epa-clean-water-rule-goes-too-far-72787">agricultural ditches and canals</a>, which might obligate some farmers and ranchers to apply for Section 404 permits. It could also ensure oversight of polluters who discharge pollutants upstream of federally protected waters.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1531915211766124544"}"></div></p>
<p>The Sacketts assert that the permitting process imposes <a href="https://www.supremecourt.gov/DocketPDF/21/21-454/220716/20220411143433423_FINAL%20Sackett%20Opening%20Brief.pdf">significant costs, delays and potential restrictions</a> on property use. In response, the Biden administration contends that most landowners can proceed under general permits that impose <a href="https://www.supremecourt.gov/DocketPDF/21/21-454/227721/20220610173641467_21-454bsUnitedStates.pdf">relatively modest costs and burdens</a>. </p>
<p>In my view, this court’s <a href="https://www.nytimes.com/2022/06/30/us/supreme-court-epa-administrative-state.html">anti-regulatory bent</a> – and the fact that no other justices joined Kennedy’s concurring Rapanos opinion – suggest that this case will produce a narrow reading of “waters of the United States.” Such an interpretation would undercut clean water protections across the country. </p>
<p>If the court requires a continuous surface connection, federal protection would no longer apply to many areas that critically affect the water quality of U.S. rivers, lakes and oceans – including seasonal streams and wetlands that are near or intermittently connected to larger water bodies. It might also mean that building a road, levee or other barrier separating a wetland from other nearby waters may be enough to remove an area from federal protection.</p>
<p>Congress could clarify what the Clean Water Act means by “waters of the United States,” but <a href="https://sgp.fas.org/crs/misc/R43943.pdf">past efforts to legislate a definition have fizzled</a>. And today’s closely divided Congress is unlikely to fare any better. The court’s ruling in Sackett could offer the final word on this issue for the foreseeable future.</p><img src="https://counter.theconversation.com/content/185282/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Albert C. Lin was a trial attorney for the Environment and Natural Resources Division of the U.S. Department of Justice from 1998 to 2003. He served as a law clerk to the Honorable Merrick Garland of the U.S. Court of Appeals for the D.C. Circuit and to the Honorable James Browning of the U.S. Court of Appeals for the Ninth Circuit. </span></em></p>The Supreme Court opens its 2022-2023 session with a high-profile case that has major implications for both wildlife and landowners.Albert C. Lin, Professor of Law, University of California, DavisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1869642022-07-18T09:06:58Z2022-07-18T09:06:58ZFive ways to help wildlife in heatwaves<p>Extremely hot weather is becoming more common. The top ten warmest years since 1884 all happened <a href="https://rmets.onlinelibrary.wiley.com/doi/10.1002/joc.7285">in the last two decades</a>. While experts can help people take adequate precautions to beat the heat, who’s looking out for the rest of the animal kingdom?</p>
<p>Hot temperatures are uncomfortable and potentially deadly for wildlife too. Fortunately, you can give a helping hand with a few easy steps.</p>
<h2>1. Provide water</h2>
<p>Hot weather can be great for some wildlife. Butterfly populations in the UK tend to bounce back from <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2656.2001.00480.x">hot and dry summers</a>, possibly because this increases the survival of their larvae. </p>
<p>But even heat-loving species can only thrive if they can also find <a href="https://theconversation.com/wildlife-winners-and-losers-in-britains-summer-heatwave-100408">enough to drink</a>. Even if you don’t have a garden, putting out a shallow dish of water will benefit a wide variety of wildlife. Add marbles or stones to it so that butterflies and bees can climb out if they fall in. </p>
<figure class="align-center ">
<img alt="A honeybee sips from the edge of a blue water dish filled with pebbles." src="https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=272&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=272&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=272&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=342&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=342&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474283/original/file-20220715-20-330cip.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=342&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Parched: insects need to stay hydrated too.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/honeybee-drinking-water-bowl-light-expanded-2019263285">BernadetteB/Shutterstock</a></span>
</figcaption>
</figure>
<p>A shallow dish on the ground might attract hedgehogs or foxes, and one placed higher up could serve as a makeshift birdbath. If you’re feeling more ambitious, you could create a miniature pond. It’s possible to make a simple one from <a href="https://www.wildlifetrusts.org/actions/how-create-mini-pond">an old washing-up bowl</a>. </p>
<p>You don’t even need to dig a hole if you include a ramp from the ground. Add gravel and rocks, plus logs or larger stones, then fill with rainwater (<a href="https://www.screwfix.com/c/outdoor-gardening/water-butts/cat1660006">a water butt</a> is useful for collecting and storing it). Include a few <a href="https://www.squiresgardencentres.co.uk/news/best-pond-plants/">pond plants</a>, such as <a href="https://www.wildlifetrusts.org/wildlife-explorer/wildflowers/spiked-water-milfoil">spiked water milfoil</a>, to oxygenate the water. You can find these at your local garden centre.</p>
<p>Rare <a href="https://www.sciencedirect.com/science/article/pii/S0003347200916270">natterjack toads</a> cannot detect new sources of water, so they can only find ponds they have visited before. But many other animals are able to <a href="https://www.sciencedirect.com/science/article/pii/S0003347285701273">sense sources of water</a> from far away. That’s why it’s important to drain or cover paddling pools overnight to prevent any animals <a href="https://www.hedgehogstreet.org/garden-hazards/">climbing in and drowning</a>.</p>
<h2>2. Provide shelter</h2>
<p>It’s much cooler out of the sun. You can help animals by offering them somewhere cool to rest. A pile of logs in a shady corner will have places for insects to hide (and present a tasty snack bar for larger wildlife). Heatwaves are not the time to trim your garden either – leave any plants uncut. They’ll provide shelter, and food if they’ve gone to seed.</p>
<figure class="align-center ">
<img alt="A pile of logs in a garden." src="https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=405&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=405&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=405&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=509&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=509&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474284/original/file-20220715-22-karcgh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=509&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A cool retreat.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/pile-wood-logs-garden-431335075">Allik/Shutterstock</a></span>
</figcaption>
</figure>
<h2>3. Provide food</h2>
<p>Leaves, fruits, seeds and roots are all food for different animals to eat. But the hot weather will be making plants wilt. Make sure flowers and berry-producing plants survive the heatwave by keeping them well-watered. If you normally feed the birds, make sure your feeders are well stocked.</p>
<h2>4. Create habitats</h2>
<p>As well as helping animals in immediate heatwaves, you can also do things for the long term. Many UK species are on the move as the climate warms, shifting the areas they are <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.12823">usually found in</a>. For example, between 1981 and 2000, European curlews (Europe’s largest and perhaps most distinctive wading bird with its curved, slender beak) moved <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2008.01666.x">119 km north-east</a>. </p>
<p>By analysing the movements of UK invertebrates over 40 years, scientists discovered that the species which eventually found new <a href="https://www.nature.com/articles/s41598-019-51582-2">suitable habitats</a> moved further than those which were restricted by fewer rarer habitats they depended on. You can help make more of these migrations a success by making your local area more accommodating for a wide range of species.</p>
<p>For example, plant bee-friendly flowers such as <a href="https://peerj.com/articles/3066/">sage or lavender</a> in window boxes and on balconies. If you have a lawn, why not turn it into a wildflower meadow? These habitats are more tolerant of drought the <a href="https://www.sciencedirect.com/science/article/pii/S0169204610001519?via%3Dihub">more species they contain</a>. They mean better for wildlife and less mowing for you. </p>
<p>If you have the space, adding a pond will give refuge to amphibians <a href="https://www.conservationevidence.com/actions/869">like frogs and newts</a>. Just make sure that at <a href="https://www.wildlifetrusts.org/actions/how-build-pond">least one side is shallower</a> to allow larger animals like squirrels or hedgehogs to climb out if they fall in.</p>
<hr>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-make-your-lawn-wildlife-friendly-all-year-round-tips-from-an-ecologist-183692">How to make your lawn wildlife friendly all year round – tips from an ecologist</a>
</strong>
</em>
</p>
<hr>
<h2>5. Reduce the heat</h2>
<p>Compared to plants, surfaces like artificial lawns and concrete slabs absorb more heat in the day and release that heat to the air at night. When in the sun, concrete paving can be <a href="https://www.sciencedirect.com/science/article/pii/S1618866712000611">more than 20°C hotter</a> than grass – too hot for us or wildlife to stand on. So why not replace hard and artificial surfaces with plants?</p>
<p>Shading from trees can reduce surface temperatures <a href="https://www.nature.com/articles/s41467-021-26768-w">by around 10°C</a>, so planting a native tree in your garden would cool you and wildlife. The elder (<em>Sambucus nigra</em>) in my garden provides berries and flowers which are great for wildlife, and grows a couple of metres each year. </p>
<p>Elders can also be pruned to suit the size of your garden too – either as a bush or a tree. If you plant one soon it could be offering shade to your garden and shelter for nesting birds by next summer.</p>
<hr>
<figure class="align-right ">
<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><strong><em>Don’t have time to read about climate change as much as you’d like?</em></strong>
<br><em><a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeTop">Get a weekly roundup in your inbox instead.</a> Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. <a href="https://theconversation.com/uk/newsletters/imagine-57?utm_source=TCUK&utm_medium=linkback&utm_campaign=Imagine&utm_content=DontHaveTimeBottom">Join the 10,000+ readers who’ve subscribed so far.</a></em></p>
<hr><img src="https://counter.theconversation.com/content/186964/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sarah Papworth has received funding from the National Geographic Society, the Natural Environment Research Council, the Zoological Society of London and the Royal Society for the Protection of Birds. She is a member of the Green Party. </span></em></p>If you’re hot, so are your four-legged neighbours.Sarah Papworth, Senior Lecturer in Conservation Biology, Royal Holloway University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1685452022-01-20T13:44:50Z2022-01-20T13:44:50ZBeavers offer lessons about managing water in a changing climate, whether the challenge is drought or floods<figure><img src="https://images.theconversation.com/files/440331/original/file-20220111-21389-ltiaq3.jpeg?ixlib=rb-1.1.0&rect=18%2C18%2C4007%2C2999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Wetlands created by beavers, like this one in Amherst, Massachusetts, store floodwaters and provide habitat for animals and birds.</span> <span class="attribution"><span class="source">Christine Hatch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>It’s no accident that both the <a href="https://web.mit.edu/graphicidentity/tim-the-beaver.html">Massachusetts Institute of Technology</a> and the <a href="https://identity.caltech.edu/logoseal/athletics">California Institute of Technology</a> claim the beaver (<em>Castor canadensis</em>) as their mascots. Renowned engineers, beavers seem able to dam any stream, building structures with logs and mud that can flood large areas. </p>
<p>As climate change causes extreme storms in some areas and intense drought in others, scientists are finding that beavers’ small-scale natural interventions <a href="https://www.chelseagreen.com/product/eager-paperback/">are valuable</a>. In dry areas, beaver ponds restore moisture to the soil; in wet zones, their dams and ponds can help to slow floodwaters. These ecological services are so useful that land managers are translocating beavers <a href="https://www.theguardian.com/environment/2021/feb/23/beavers-native-american-tribes-washington-california">in the U.S.</a> and <a href="https://www.bbc.com/future/article/20210713-the-beavers-returning-to-the-desert">the United Kingdom</a> to help restore ecosystems and make them more resilient to climate change. </p>
<p>Scientists estimate that <a href="https://doi.org/10.1088/1748-9326/abd34e">hundreds of millions of beavers</a> once dammed waterways across the Northern Hemisphere. They were <a href="https://ecwpress.com/products/once-they-were-hats">hunted nearly to extinction for their fur</a> in the 18th and 19th centuries in Europe and North America but are <a href="https://www.nationalgeographic.com/animals/article/beavers-climate-change-conservation-news">making comebacks today</a> in many areas. As a <a href="https://www.researchgate.net/profile/C-Hatch">geoscientist specializing in water resources</a>, I think it’s important to understand how helpful beavers can be in the <a href="https://methowbeaverproject.org">right places</a> and to find ways for humans to coexist with them in developed areas.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/6lT5W32xRN4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scientists are studying ways to use beavers to mitigate wildfire and drought risks in the western U.S.</span></figcaption>
</figure>
<h2>How beavers alter landscapes</h2>
<p>Beavers <a href="https://www.sciencefocus.com/nature/why-do-beavers-build-dams/">dam streams to create ponds</a>, where they can construct their dome-shaped lodges in the water, keeping predators at a distance. When they create a pond, many other effects follow. </p>
<p>Newly flooded trees die but remain standing as bare “snags” where birds nest. The diverted streams create complicated interwoven channels of slow-moving water, tangled with logs and plants that provide hiding places for fish. The messy complexity behind a beaver dam creates many different kinds of habitats for creatures such as fish, birds, frogs and insects. </p>
<p>Human dams often <a href="https://www.nwcouncil.org/reports/columbia-river-history/fishpassage">block fish passage</a> upstream and downstream, even when the dams <a href="https://www.scientificamerican.com/article/upstream-battle-fishes-shun-modern-dam-passages-population-declines/">include fish ladders</a>. But <a href="https://doi.org/10.1111/j.1467-2979.2011.00421.x">studies have shown</a> that fish have no trouble migrating upstream past beaver dams. One reason may be that the fish can rest in slow pools and cool pond complexes after navigating the tallest parts of the dams. </p>
<p>The slow-moving water behind beaver dams is very effective at trapping sediment, which drops to the bottom of the pond. Studies measuring total organic carbon in active and abandoned beaver meadows suggest that before the 1800s, active and abandoned beaver ponds across North America <a href="https://doi.org/10.1002/grl.50710">stored large amounts of carbon</a> in sediment trapped behind them. This finding is relevant today as scientists look for ways to <a href="https://theconversation.com/what-the-world-needs-now-to-fight-climate-change-more-swamps-99198">increase carbon storage in forests and other natural ecosystems</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Curved dam in a marsh, made of wood, grass and mud." src="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/441410/original/file-20220118-15-d1qkya.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">A beaver dam in Mason Neck State Park in Lorton, Virginia, creates a pond behind it that can spread out and slow down floodwaters during a storm.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/BDNqd1">Virginia State Parks</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Beavers may persist in one location for decades if they aren’t threatened by bears, cougars or humans, but they will move on if food runs out near their pond. When abandoned beaver dams fail, the ponds drain and gradually become grassy meadows as plants from the surrounding land seed them. </p>
<p>Dried meadows can serve as floodplains for nearby rivers, allowing waters to spill out and provide forage and spawning areas for fish during high flows. Floodplain meadows are <a href="https://www.fws.gov/oregonfwo/toolsforlandowners/riverscience/documents/brg%20v.1.0%20final%20reduced.pdf">valuable habitat</a> for ground-nesting birds and other species that depend on the river. </p>
<h2>The value of slowing the flow</h2>
<p>As human settlements expand, people often wish to make use of every acre. That typically means that they want either land that is solid and dry enough to farm or waterways they can navigate by boat. To create those conditions, humans remove floating logs from streams and install drains to draw water off of fields and roads as quickly and efficiently as possible. </p>
<p>But covering more and more land surface with barriers that don’t absorb water, such as pavement and rooftops, means that water flows into rivers and streams more quickly. Rainfall from an average storm can produce an intense river flow that <a href="https://extension.umass.edu/riversmart/">erodes the banks and beds of waterways</a>. And as climate change <a href="https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/question-13/">fuels more intense storms in many places</a>, it will amplify this destructive impact.</p>
<p>Some developers limit this kind of damaging flow by using <a href="https://basc.pnnl.gov/resource-guides/swales-drains-and-site-grading-stormwater-control">nature-based engineering principles</a>, such as “ponding” water to intercept it and slow it down; spreading flows out more widely to reduce the water’s speed; and designing swales, or sunken spots, that allow water to sink into the ground. Beaver wetlands do all of these things, only better. Research in the United Kingdom has documented that beaver activity can <a href="https://doi.org/10.1016/j.scitotenv.2016.10.122">reduce the flow of floodwaters from farmlands by up to 30%</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1443636906487697416"}"></div></p>
<p>Beaver meadows and wetlands also <a href="https://kingcounty.gov/services/environment/animals-and-plants/beavers/Benefits.aspx">help cool the ground around and beneath them</a>. Wet soil in these zones contains a lot of organic matter from buried and decayed plants, which holds onto moisture longer than soil formed only from rocks and minerals. In my <a href="https://www.livingobservatory.org/learning-report">wetland research</a>, I have found that after a storm, water entering the ground passes through pure mineral sand in hours to days but can remain in soils that are 80%-90% organic matter for as long as a month. </p>
<p>Cool, wet soil also serves as a buffer against wildfires. Recent studies in the western U.S. have found that vegetation in beaver-dammed river corridors is <a href="https://doi.org/10.1002/eap.2225">more fire-resistant</a> than in areas without beavers because it is well watered and lush, so it doesn’t burn as easily. As a result, areas near beaver dams provide <a href="https://www.sagegrouseinitiative.com/beaver-breaks-how-beavers-and-low-tech-riparian-restoration-help-reduce-impacts-from-fire/">temporary refuge for wildlife</a> when <a href="https://doi.org/10.1002/bes2.1795">surrounding areas burn</a>.</p>
<h2>Making room for beavers</h2>
<p>The ecological services that beavers provide are most valuable in zones where nobody minds if the landscape changes. But in the densely developed eastern U.S., where I work, it’s hard to find open areas where beaver ponds can spread out without flooding ditches or roads. Beavers also topple expensive landscaped trees and will feed on some cultivated crops, such as <a href="https://agrilife.org/txwildlifeservices/files/2016/07/fs_beaver.pdf">corn and soybeans</a>.</p>
<p>Beavers are frequently blamed for flooding in developed areas, even though <a href="https://www.gazettenet.com/earth-matters-are-beavers-to-blame-for-flooding-damage-41825413">the real problem often is road design, not beaver dams</a>. In such cases, removing the beavers doesn’t solve the problem. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pipe in the middle of a flooded rural road" src="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/440340/original/file-20220111-19-svgy1g.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"></a>
<figcaption>
<span class="caption">Debris carried by intense rains in July 2021 overtopped a beaver dam (still standing in the background) and washed out this undersized 3-foot culvert in western Massachusetts. It has since been replaced by a more resilient 9-foot structure.</span>
<span class="attribution"><span class="source">Christine Hatch</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><a href="https://www.fs.fed.us/t-d/pubs/pdfpubs/pdf05772830/pdf05772830dpi300.pdf">Culvert guards</a>, fences and other exclusion devices can keep beavers a safe distance from infrastructure and maintain pond heights at a level that won’t flood adjoining areas. Road crossings over streams that are designed to <a href="https://streamcontinuity.org">let fish and other aquatic animals through instead of blocking them</a> are beaver-friendly and will be resilient to climate change and extreme precipitation events. If these structures are large enough to let debris pass through, then beavers will build dams upstream instead, which can help catch floodwaters.</p>
<p>[<em>Over 140,000 readers rely on The Conversation’s newsletters to understand the world.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-140ksignup">Sign up today</a>.]</p>
<p>A growing body of research shows that setting aside pockets of land for beavers is good for wetland ecosystems, biodiversity and rivers. I believe we can learn from beavers’ water management skills, coexist with them in our landscapes and incorporate their natural engineering in response to weather and precipitation patterns disrupted by climate change.</p><img src="https://counter.theconversation.com/content/168545/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Hatch has trained workers at the Massachusetts Department of Transportation on Rivers and Roads, mainly free of charge as public outreach work.
</span></em></p>Beavers in our landscapes have great potential to provide small-scale adaptations to climate change – if humans can figure out how to live with them.Christine E. Hatch, Professor of Geosciences, UMass AmherstLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1642272021-07-15T16:46:43Z2021-07-15T16:46:43ZExtreme heat waves are putting lakes and rivers in hot water this summer<figure><img src="https://images.theconversation.com/files/411299/original/file-20210714-21-1bygcs3.jpg?ixlib=rb-1.1.0&rect=36%2C80%2C4837%2C2917&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">River fish like trout swim close to the river surface as water temperatures rise.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Extreme heat waves have blanketed the <a href="https://www.washingtonpost.com/world/2021/06/30/climate-change-heat-politics/">Pacific Northwest, Siberia</a>, <a href="https://greekreporter.com/2021/06/30/heat-waves-greece-around-world-break-new-records/">Greece</a>, <a href="https://www.aljazeera.com/news/2021/7/1/interactive-mapping-hottest-temperatures-around-world">the Middle East</a>, <a href="https://www.telegraph.co.uk/global-health/climate-and-people/hotter-human-body-can-handle-pakistan-city-broils-worlds-highest/">Southeast Asia</a> and <a href="https://www.nytimes.com/2021/07/09/upshot/record-breaking-hot-weather-at-night-deaths.html">other regions</a> this summer, with <a href="https://www.bbc.com/news/world-us-canada-57788118">temperatures approaching</a> and exceeding 50 C.</p>
<p>As temperatures near outdoor survival thresholds, individuals who do not have easy access to air conditioning or cooling stations, or are <a href="https://www.theguardian.com/commentisfree/2021/jul/07/global-heating-climate-crisis-heat-two-classes">unable to flee</a>, may <a href="https://doi.org/10.1038/s41558-021-01058-x">succumb to heat waves</a>. </p>
<p>These <a href="https://doi.org/10.1073/pnas.1101766108">climate extremes are becoming more frequent</a>. But as tragic as they are to human health, they are only part of a larger climate catastrophe story — the wide-scale damage to the ecosystems that people depend upon, including agriculture, fisheries and freshwater.</p>
<p>Most wildlife cannot seek refuge from extreme heat. An estimated <a href="https://www.cbc.ca/news/canada/british-columbia/intertidal-animals-ubc-research-1.6090774">one billion marine animals may have perished</a> during the heatwave this past June in the Pacific Northwest alone.</p>
<h2>Fisheries in hot water</h2>
<p>Many people may perceive lakes and rivers to be refuges from unprecedented heat, but freshwater systems are no less sensitive. <a href="https://www.independent.co.uk/climate-change/news/alaska-heatwave-salmon-rivers-july-temperatures-climate-change-a9063461.html">Heat waves have killed thousands of fish in Alaska</a> as temperatures exceeded the lethal limit for coldwater fishes.</p>
<p>This year’s hot and dry summer could <a href="https://www.sacbee.com/news/california/water-and-drought/article252650328.html">collapse the salmon fishery in the Sacramento River in California</a>. In British Columbia and Yukon, salmon numbers have declined by as much as 90 per cent and have led the federal government to shut down <a href="https://www.timescolonist.com/sports/add-an-event/ottawa-to-close-about-60-per-cent-of-commercial-salmon-fisheries-to-conserve-stocks-1.24336891">60 per cent of the commercial and First Nations communal salmon fishery</a>. </p>
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<strong>
Read more:
<a href="https://theconversation.com/how-drought-affects-freshwater-fish-109781">How drought affects freshwater fish</a>
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<p>Coldwater fish, such as trout and salmon, are being squeezed out of their cool, well-oxygenated, deep-water habitat. As water contains less oxygen at higher water temperatures, this forces the fish to move into nearshore regions. While these shallower waters may be better oxygenated, they are even warmer and may exceed thermal tolerances of coldwater species. </p>
<p>By the same token, invasive fishes such as smallmouth bass are thriving in warmer temperatures and displacing native Canadian fishes like walleye and lake trout.</p>
<h2>Water is on the move — too little and too much</h2>
<p>The combination of a warming climate, drought and human activities, including irrigation for agriculture, can have drastic consequences for both the quality and quantity of our freshwater supply — ultimately leading to shortages of potable water.</p>
<p>By the end of the century, <a href="https://doi.org/10.1038/s41561-018-0114-8">evaporation is projected to increase by 16 per cent globally</a>. Lakes closer to the equator, which are already experiencing the highest evaporation rates, are expected to experience the greatest increase. </p>
<p>In regions with seasonal ice cover, evaporation rates can increase with warmer air temperatures and when ice cover is shorter or lost completely. This essentially “lifts the lid” on a lake during winter and could potentially lead to year-round evaporation, accelerating the rate at which water is lost. Salts and nutrients are concentrated in the remaining water, leading to further decline in water quality. </p>
<figure class="align-center ">
<img alt="The dry bed of an evaporated pond in Arctic Canada." src="https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410843/original/file-20210712-23-jhxnd.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">Beach Ridge Pond, from Ellesmere Island in Nunavut, now completely evaporates in the summer because of accelerated climate warming.</span>
<span class="attribution"><span class="source">(MSV Douglas)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Potable water in countries with limited freshwater are <a href="https://www.nationalgeographic.com/magazine/article/drying-lakes-climate-change-global-warming-drought">seeing their supply dwindle even further</a>, including the <a href="https://www.mentalfloss.com/article/56732/10-lakes-are-disappearing-or-already-gone">Aral Sea in Kazakhstan and Lake Chad in central Africa</a>. <a href="https://theconversation.com/lake-poopo-why-bolivias-second-largest-lake-disappeared-and-how-to-bring-it-back-152776">Lake Poopó was once the second-largest lake in Bolivia with an area of 3,000 square kilometres, but dried up completely in 2015</a>. Even in water-rich areas like the Arctic, <a href="https://doi.org/10.1073/pnas.0702777104">shallow ponds</a>, including some <a href="https://www.doi.org/10.1126/science.1108142">ponds formed when ice-rich permafrost thaws</a>, are already drying out. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-scientists-are-using-drones-to-lower-the-risk-of-catastrophic-flooding-from-large-glacial-lakes-158689">How scientists are using drones to lower the risk of catastrophic flooding from large glacial lakes</a>
</strong>
</em>
</p>
<hr>
<p>On the other hand, ice-dammed glacial lakes in both polar and alpine regions are sensitive to outburst floods as dams melt, potentially flooding downstream ecosystems and the communities that depend on them, including population-rich areas such as <a href="https://doi.org/10.1038/s41558-021-01028-3">in the Himalayas</a> and <a href="https://www.nature.com/articles/s41561-021-00686-4.epdf?sharing_token=dvnb89oERd0OajwLFZXscNRgN0jAjWel9jnR3ZoTv0NpVdznzVXpU0m-Rai-gGLEEEq67k5aPfFB5nX1DG8RWzIQ8JaW1ei3lTOobV6C9kc-cdxEn0U_fZkPVphxffsgbZHEr8tm8Fu_rFSvw3ED98_HmklXtjMtETMSzzRoYyM%3D">Andes</a>. Climate change is a crisis multiplier and threatens to make water scarcity or flooding an impending reality for increasingly more people.</p>
<h2>Algal blooms on the rise</h2>
<p>Warmer summers, coupled with <a href="https://doi.org/10.1139/facets-2020-0022">intense storms</a> that deliver large quantities of nutrients and pollutants in bursts, are creating the perfect conditions for <a href="https://doi.org/10.1038/s41586-019-1648-7">earlier, more frequent and intense algal blooms</a>. Harmful toxin-producing cyanobacteria (blue-green algae that frequently form floating surface blooms) can lead to mass mortality of fish and birds, as well as pose a serious health threat for cattle, pets, wildlife and humans.</p>
<p>In 2014, over half a million people could not use their water supply in Toledo, Ohio, because of a <a href="https://www.nationalgeographic.com/science/article/140804-harmful-algal-bloom-lake-erie-climate-change-science">toxic algal bloom in Lake Erie</a>. Lake Taihu, China, which <a href="https://doi.org/10.1007/s00267-009-9393-6">supplies water to 40 million people</a> often has blooms so large that they can be <a href="https://apps.sentinel-hub.com/sentinel-playground/?source=S2&lat=31.23217880603803&lng=120.10940551757812&zoom%22%22">detected from space</a> and leave millions of people in a drinking water supply crisis. </p>
<figure class="align-center ">
<img alt="A lake near Parry Sound, Ont., covered in algal bloom." src="https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/410844/original/file-20210712-70646-12ggbkz.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">An algal bloom in a lake near Parry Sound, Ont., located on the Canadian Shield.</span>
<span class="attribution"><span class="source">(Andrew Paterson/Ontario Ministry of the Environment, Conservation and Parks)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In Ontario, there are now <a href="https://doi.org/10.1007/s10933-019-00074-4">reports of algal blooms</a> in formerly pristine northern lakes occurring as late as November. Study after study now links warmer conditions and the associated lake changes as important contributing factors to toxic blooms.</p>
<h2>Rapid change requires rapid responses</h2>
<p>Climatic extremes are now occurring more frequently and with greater intensity than were <a href="https://theconversation.com/just-how-hot-will-it-get-this-century-latest-climate-models-suggest-it-could-be-worse-than-we-thought-137281">predicted by even the most pessimistic climate models</a>. We are already crossing ecosystem thresholds and tipping points that were not even projected to occur until the end of this century. </p>
<p>Climatic extremes will not appear gradually, but impacts will be felt quickly and often without warning, leaving little time for adaptation. We need to immediately <a href="https://www.cbc.ca/news/canada/lytton-fire-climate-emergency-preparedness-1.6096370">develop and implement evidence-based climate adaptation plans</a>, so that we are prepared for the inevitable emergencies already underway, including massive wildfires, coastal and <a href="https://www.reuters.com/business/environment/thirty-missing-germany-house-collapses-heavy-rain-media-2021-07-15/">local flooding</a>, disruption of food supplies and freshwater shortages.</p>
<p>The apocalyptic future, once portrayed only in books and movies, is becoming our reality and the time for assessing our options is running out. Numerous studies have shown the benefits of reducing greenhouse gas emissions. Human innovation and originality, coupled with a sense of urgency, are required to lessen future impacts.</p>
<p>Without mitigation efforts, we must prepare for the fallout of the developing climate catastrophe and protect our citizens and ecosystems.</p><img src="https://counter.theconversation.com/content/164227/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sapna Sharma receives funding from NSERC, Ontario Ministry of Economic Development and Innovation, Ontario Ministry of Environment, Conservation and Parks, Genome Canada, and the York University Research Chair Program. She is affiliated with the Royal Canadian Institute for Science. </span></em></p><p class="fine-print"><em><span>John P. Smol receives funding from NSERC and the Canada Research Chairs program.</span></em></p><p class="fine-print"><em><span>Iestyn Woolway 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>The growing frequency of climate extremes affected human health and caused wide-scale damages to the ecosystems that people depend upon, including agriculture, fisheries and freshwater.Sapna Sharma, Associate Professor and York University Research Chair in Global Change Biology, York University, CanadaIestyn Woolway, Research Fellow, Climate Office, European Space AgencyJohn P. Smol, Distinguished University Professor and Canada Research Chair in Environmental Change, Queen's University, OntarioLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1545782021-02-24T11:11:34Z2021-02-24T11:11:34ZHow we turned a golf course into a haven for rare newts, frogs and toads<figure><img src="https://images.theconversation.com/files/385907/original/file-20210223-14-cnfbpy.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4992%2C3325&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/common-frog-rana-temporaria-single-reptile-167747600">Erni/Shutterstock</a></span></figcaption></figure><p>Around two in five amphibian species are <a href="https://www.iucnredlist.org/">threatened with extinction</a> around the world. In Britain, all of our native frog, toad and newt species have <a href="https://www.newnaturalists.com/products/amphibians-reptiles-collins-new-naturalist-library-book-87-9780007308620/">declined since 1945</a>, with one species – <a href="https://www.arc-trust.org/pool-frog">the pool frog</a> – dying out in the 1990s. Climate change, disease and invasive species all have a hand in this, but one of the greatest <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.14739">pressures</a> facing amphibians is the loss of their habitat. As more land is developed for houses, roads and shops, those wild and marshy patches where amphibians thrive are scrubbed from maps.</p>
<p>Setting aside land in nature reserves can help protect biodiversity, though on their own, these islands of natural habitat cannot provide enough space to revive wider communities of wildlife. Since much of the UK’s land is <a href="https://www.countryfile.com/news/who-owns-england-history-of-englands-landownership-and-how-much-is-privately-owned-today/">in private hands</a>, conservationists need to think about how nature can be encouraged on land occupied by businesses, including farms, estates and golf courses.</p>
<p>We are two ecologists who are dedicated to restoring habitats for amphibians wherever we can. By working with land managers of all kinds, we’re figuring out how to repopulate modern landscapes with these creatures. Here’s what we’ve learned so far.</p>
<h2>Getting landowners onside</h2>
<p>Perhaps the most famous amphibians in literature are the unfortunate newts and frogs of Shakespeare’s Macbeth, which end up in the witches’ brew on <a href="https://forreslocal.com/visiting/what-to-see-and-do-in-forres/macbeth/">Forres heath</a> in the Scottish Highlands. Over 400 years later, <a href="https://link.springer.com/article/10.1007/s10344-014-0863-7">our own research</a> has shown that populations of great-crested newts face a different kind of toil and trouble. </p>
<p>For centuries, ponds existed on British farmland to water livestock, which offered habitats for amphibians to breed in. But nowadays, sheep and cattle drink from troughs and many wetlands which once sustained wildlife have been drained to create timber plantations and golf courses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A large and speckled newt on dry soil." src="https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=604&fit=crop&dpr=1 754w, https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=604&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/384495/original/file-20210216-13-5pe7qu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=604&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 Highland great-crested newt.</span>
<span class="attribution"><span class="source">David O’Brien</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Any plan to halt the decline of Britain’s amphibians must be compatible with different types of land use. So in 2014, we sat down with people working in forestry, farming and a local golf club to develop a plan for <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1002/2688-8319.12038">restoring 25 ponds</a> in the Scottish Highlands, focusing on Forres and the areas around Inverness which have seen the greatest loss of ponds.</p>
<p>Rather than imposing rules on land managers, we talked with them about their interests and what they saw as important. Pride in their heritage and the opportunity to be seen as good stewards of the land were what most motivated those we spoke to. </p>
<p>One of the sites had been in the owner’s family since the 17th century, and the farmers felt a connection to their land and the wildlife that lived on it. “I may never notice the newts in the pond,” one said. “But I’m glad to know they’re there.”</p>
<p>The golf pro, who had grown up near the course where he now worked, remembered catching newts and tadpoles as a child and wanted his grandchildren to be able to see them too. He used his influence with the club committee to convince them that a pond wouldn’t just be good for nature, but would improve the appearance of the course. </p>
<p>The ground staff joined in to manage vegetation around the ponds to ensure places for the animals to feed outside of the breeding season. Whenever we now survey this pond for species, we’re greeted by golfers who’re proud of “their frogs and newts” and want to know how they’re doing.</p>
<h2>Creating the perfect pond</h2>
<p>We had permission to start restoring habitats on private land, but how can you tell if what you’re making is right for the species you’re trying to help? Luckily, we had a pretty good idea of what makes the perfect pond because we had 25 years’ worth of data gathered by citizen scientists, as well as <a href="https://link.springer.com/article/10.1007%2Fs10750-016-3053-7">our own observations</a> of ponds filled with amphibians. </p>
<p>Everything from the slope of the nearby bank, the presence of fish and insects and the kind of plants which fringed the pool were carefully considered. We then designed ponds ideal for all five amphibian species native to the Scottish Highlands – the common frog, common toad, and smooth, palmate and great-crested newts.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A pond amid a boggy scrubland with trees in the background." src="https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/384494/original/file-20210216-13-1vaj7ed.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">One of the first new ponds to be colonised, which now has breeding common frogs and three newt species.</span>
<span class="attribution"><span class="source">David O’Brien</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Newts rarely travel more than a few hundred metres, and if the nearest pond is further away or if there’s a barrier like a busy road, they won’t be able to move between ponds. This can lead to inbreeding and leave populations vulnerable to extinction. If a pond dries up for several breeding seasons then it won’t be recolonised once it’s refilled with water. For this reason, we restored former ponds and created new ones close to occupied ponds.</p>
<p><a href="https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1002/2688-8319.12038">Five years on</a>, 24 out of the 25 ponds are inhabited by amphibians. After surveying our ponds and comparing them with 88 long-established ones in the area, we were delighted to find that not only were all five species breeding in them, including the locally rare great-crested newt, but on average our ponds held more species than the pre-existing ones. We’ve stayed in contact with all the land managers and they remain committed to conservation. </p>
<p>And the one pond with no amphibians? Unfortunately, an error led us to construct a pond that wasn’t quite right. But we accidentally created the perfect pond for a rare dragonfly called the white-faced darter instead. Now we can’t wait to find out what other species might have made our ponds their homes.</p><img src="https://counter.theconversation.com/content/154578/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David O'Brien works for NatureScot (formerly Scottish Natural Heritage) which funded part of this project alongside Forestry and Land Scotland.</span></em></p><p class="fine-print"><em><span>Robert Jehle 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>Britain’s native amphibians are in steep decline thanks to wetlands disappearing and ponds drying up.David O'Brien, PhD Candidate in Wildlife Biology, University of SalfordRobert Jehle, Reader in Population Biology, University of SalfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1509012021-01-05T20:14:41Z2021-01-05T20:14:41ZWhat to feed ducks – according to science<figure><img src="https://images.theconversation.com/files/372602/original/file-20201202-13-yg85tx.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4665%2C3110&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/cute-little-boy-feeding-ducks-pond-84142186">Max Topchii/Shutterstock</a></span></figcaption></figure><p>The simple things in life sometimes bring the greatest joy – like feeding the ducks at your local pond. The next time you pay your feathered friends a visit, consider introducing some variety into the food you give them. Just like for us humans, a balanced diet is important for wild animals. The large amounts of bread that people feed wild birds may be well-intentioned, but they could be doing them harm.</p>
<p>Feeding wild birds means that they need to spend less time foraging, which allows them to build their strength and produce more chicks. But this could also make birds dependent on the food humans provide and cause malnutrition, as the nutritional value of processed food is likely to differ greatly from their natural diet. By encouraging birds to congregate around a food source, there is also an <a href="https://theconversation.com/why-you-may-need-to-encourage-social-distancing-around-your-bird-feeder-137134">increased risk of disease transmission</a>.</p>
<p>We recently embarked on <a href="https://pubmed.ncbi.nlm.nih.gov/32949068/">a study</a> of birds living in seven public areas throughout Amsterdam, including squares and parks. We wanted to understand how feeding ducks and other wild birds affected their health, so we examined what kind of foods people were feeding them, and compared its nutritional value with the nutritional requirements we’d expect for each species.</p>
<figure class="align-center ">
<img alt="A pair of hands tear a bit of bread with a duck near a pond in the background." src="https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373090/original/file-20201204-15-qn650e.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">
<figcaption>
<span class="caption">Just say no!</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-girl-feeding-ducks-white-bread-472598035">Nielskliim/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Why bread is bad</h2>
<p>Bread was by far the most popular choice of food offered to wild birds, making up two-thirds of the total. Most people feed birds so as not to waste bread or meal leftovers, but for birds, it’s actually the worst option.</p>
<p>The nutritional value of bread is not a good match for the needs of wild birds. It’s deficient in amino acids, fatty acids and several vitamins and minerals, but full of carbohydrates and salt – all the stuff birds don’t need and little of what they do. If birds are overwhelmingly eating bread instead of natural options, it could lead to health problems. In many ways, this is unsurprising. Just imagine how you would feel if your diet only consisted of bread. As your new year’s resolution, avoid bread when feeding the ducks. </p>
<p>But what should you feed them instead? Here are some options, ranked from best to worst.</p>
<h2>1. Seeds and nuts</h2>
<p>Bird seed is one of the best options, but only in limited amounts – which goes for all the food in this list. Ducks should predominantly eat greens from their own environment, like grass, as well as small fish, and frogs – everything they’d usually have no trouble finding in a pond.</p>
<p>Still, seeds and nuts are a good choice because of their high nutritional value. They’re rich in fat with a high level of essential fatty acids, which means it’s wise to only feed birds with small amounts of seeds and nuts.</p>
<figure class="align-center ">
<img alt="Assorted seeds and nuts." src="https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373091/original/file-20201204-23-mg038z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">If it’s good enough for the birds in your garden, it’s good enough for ducks.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/assorted-seed-nuts-feeding-wild-birds-59171632">Meirion Matthias/Shutterstock</a></span>
</figcaption>
</figure>
<h2>2. Fruit and vegetables</h2>
<p>Vegetables, such as sweetcorn, lettuce and peas, and fruit, including apple and banana pieces, are great as a source of fibre and water. But they also provide essential vitamins. </p>
<p>The downside is that large quantities can cause stomach upset, especially fruit, but also vegetables high in carbohydrates, like carrots. Try to balance small amounts of these with seeds and nuts.</p>
<h2>3. Rice</h2>
<p>Rice, both cooked and uncooked, isn’t a bad choice. It provides a good source of energy but is quite low in nutritional value. Feeding birds with large quantities of rice can result in deficiencies in other nutrients. It’s also important to only give plain rice – never seasoned or fried rice.</p>
<p>Giving lots of uncooked rice can give ducks a sore stomach because it reacts with water in their gut. Uncooked rice is perfectly safe in small doses though – in spite of what <a href="https://www.livescience.com/32624-does-wedding-rice-make-birds-explode.html">urban myths</a> might tell you.</p>
<figure class="align-center ">
<img alt="Yellow birds peck at rice strewn on a path." src="https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373092/original/file-20201204-13-qbw868.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">Birds can have a little rice – as a treat.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/group-yellow-birds-eat-white-rice-1832966980">Alexandre Laprise/Shutterstock</a></span>
</figcaption>
</figure>
<h2>4. Leftovers</h2>
<p>Leftovers of the processed foods we like to eat – think french fries and pizza crusts – shouldn’t actually be in this list. They do for birds what fast food does for us: lots of energy, but with very little nutrition. </p>
<p>In our study, we found that leftovers were one of the top choices of people feeding ducks. But our advice – as with bread – is to avoid it altogether.</p>
<h2>Don’t overdo it</h2>
<p>Our final piece of advice is don’t overfeed. If everyone fed ducks with small quantities of a certain food, they might end up eating too much of it in the end, so variety is key.</p>
<p>We also found that people often overfeed birds. Food accumulating in a pond goes mouldy and encourages bacteria which can leach oxygen from the water and produce toxins.</p>
<p>There will inevitably be leftovers that either turn into litter or food for other animals. Based on our calculations, this surplus of food would, on average, provide enough energy to sustain 153 rats per study area.</p>
<p>Brown rats prey on the eggs of waterfowl and young ducklings. This is normal behaviour, but an abundance of rats could skew the natural balance between the species. So be careful with overfeeding, or you might actually reduce the number of ducks in your local pond.</p><img src="https://counter.theconversation.com/content/150901/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 organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Your local ducks (and other wild birds) will thank you.Ronald Jan Corbee, Assistant Professor of Veterinary Medicine, Utrecht UniversitySara Burt, Assistant Professor of Veterinary Public Health, Utrecht UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1384722020-05-19T11:58:09Z2020-05-19T11:58:09ZMoths do the pollinator night shift – and they work harder than daytime insects<figure><img src="https://images.theconversation.com/files/336046/original/file-20200519-152327-xhd0u7.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5599%2C3746&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/white-moth-night-488192602">Wildfocusphoto/Shutterstock</a></span></figcaption></figure><p>When you settle down for bed, after the birds and bees have hushed, <a href="https://books.google.co.uk/books?id=oZ90BQAAQBAJ&pg=PA112&lpg=PA112&dq=about+settling+moths&source=bl&ots=K7e-jSid8y&sig=ACfU3U1kp1JvP2u5pRR6zxDZfktv0EYlyA&hl=en&sa=X&ved=2ahUKEwj-95SQyLXpAhUyoXEKHcQcDYk4ChDoATAIegQICBAB#v=onepage&q=about%20settling%20moths&f=false">moths</a> are just starting their work. You might only see them bobbing around street lights at night, but they actually spend most of their time visiting flowers, pollinating them in the same way butterflies do during the day, while drinking nectar with their long tongues.</p>
<p>In fact, <a href="https://royalsocietypublishing.org/doi/10.1098/rsbl.2019.0877">our new research</a> found that moths visit a surprisingly diverse range of plants at night. The work these nocturnal pollinators do is bigger and more complex than many people realised, and because it happens under the cover of darkness, it’s often largely invisible to human eyes.</p>
<p>Moths were known to pollinate flowers at night, but science has only recently begun to uncover their efforts in detail. We now know <a href="https://www.tandfonline.com/doi/abs/10.1080/00222933.2013.791944">the types of flowers they visit</a> – pale-coloured flowers with an open cup or tubular shape, such as creeping buttercup or honeysuckle, which tend to emit a strong fragrance at night. We also know that they <a href="https://butterfly-conservation.org/news-and-blog/the-role-of-moths-as-nocturnal-pollinators">carry pollen</a> on their tongues. But besides that, most of what we know about pollinators, and <a href="https://blog.oup.com/2017/06/how-can-we-save-pollinators/">how to help them</a>, comes from research on daytime species such as bees, hoverflies and butterflies.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/339863/original/file-20200604-67377-17zx8nm.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">Honeysuckle flowers – irresistible to moths.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/blooming-yellow-honeysuckle-bush-flowering-whiteyellow-1417291202">Krolya25/Shutterstock</a></span>
</figcaption>
</figure>
<p>We urgently need to learn about the more mysterious pollinating insects. Among the 353 daytime pollinator species in Britain, numbers <a href="https://theconversation.com/insects-species-that-prefer-crops-prosper-while-majority-decline-114206">fell by a third</a> between 1980 and 2013. If these losses are being recorded among well studied species, what could be happening to nocturnal pollinators, whose lives we don’t know as much about? We know how valuable bees and other insects are for pollinating the crops we eat, like <a href="https://www.sciencemag.org/news/2016/02/pollinator-declines-threaten-world-s-food-supply">apples and raspberries</a>, but we’re less sure about the debt we owe moths for their tireless nighttime work.</p>
<h2>What moths get up to at night</h2>
<p>Our research focused on the edges of nine ponds surrounded by crops and hedgerows in <a href="https://www.norfolkfwag.co.uk/norfolk-ponds-project/">north Norfolk farmland</a>. We wanted to find out which flowers moths chose to visit and how they behaved, compared with the daytime habits of other insect pollinators.</p>
<p>We observed and recorded key daytime pollinators, including bees, hoverflies, and butterflies, as they visited flowers. In the evening, we used light traps to lure moths into buckets set next to ponds and, the next morning, we brought the moths to the laboratory to identify them and check their bodies for pollen.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/336049/original/file-20200519-152338-1huhbk4.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">
<figcaption>
<span class="caption">Some of the pollen grains recovered from the bodies of moths.</span>
<span class="attribution"><span class="source">Richard Elton Walton</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Researchers tend to look for the pollen moths gather on their tongues. But anyone who spends even a moment with a moth will notice their bodies are rather “furry”. <a href="https://books.google.co.uk/books?id=oZ90BQAAQBAJ&pg=PA112&lpg=PA112&dq=about+settling+moths&source=bl&ots=K7e-jSid8y&sig=ACfU3U1kp1JvP2u5pRR6zxDZfktv0EYlyA&hl=en&sa=X&ved=2ahUKEwj-95SQyLXpAhUyoXEKHcQcDYk4ChDoATAIegQICBAB#v=onepage&q=about%20settling%20moths&f=false">At rest</a>, their bodies tend to stick very close to the landing surface of the flower, meaning moths can’t help but bump into the pollen on the plant’s reproductive parts as they drink nectar, causing it to stick to them. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-is-forcing-butterflies-and-moths-to-adapt-but-some-species-cant-125829">Climate change is forcing butterflies and moths to adapt – but some species can't</a>
</strong>
</em>
</p>
<hr>
<p>With hairy bodies, bees and hoverflies <a href="https://pollinatorproject.gg/hoverflies/">tend to transport pollen</a> between the plants they visit by picking it up on their bodies. We wondered, could moths be pollinating plants in the same way?</p>
<p>We managed to trace the pollen carried by different species of moths to the plants it came from, and compared those records with the flowers that daytime pollinators visited. We found that moth food webs were incredibly complex. Moths tended to visit the same range of plant species that daytime pollinators visit, but far more species of moth were involved in the effort compared to bees and butterflies. Since moths and daytime pollinators interact with many of the same plants, moths could help fill in the gaps if some daytime species die out. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=587&fit=crop&dpr=1 600w, https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=587&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=587&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=738&fit=crop&dpr=1 754w, https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=738&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/335431/original/file-20200515-138665-azmeb2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=738&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A herald moth resting near a farmland pond.</span>
<span class="attribution"><span class="source">Richard Elton Walton</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We also found that moths interacted more regularly with some flowers, such as <a href="https://www.wildlifetrusts.org/wildlife-explorer/wildflowers/white-clover">white clover</a>, compared to daytime pollinators. This indicates they may be very important for the pollination of those particular plants, and so help sustain them for the benefit of the greater ecosystem. We also found that moths carried most of the pollen on their bodies, suggesting they transport pollen in much the same way that daytime pollinators do.</p>
<p>It’s likely that scientists have been underestimating the contribution moths make to pollination. These nocturnal creatures play a very important role in boosting the ecological health of the countryside, but even as we learn how undervalued they are, recent research suggested that moth populations in Britain are <a href="https://www.theguardian.com/environment/2019/nov/11/moth-populations-steady-decline-britain-study">shrinking by 10% each decade</a>. We should all think of the many types of plants we can grow to encourage their populations to thrive – such as <a href="http://www.mothscount.org/text/64/nectar_plants.html">forget-me-nots, primose, and jasmine</a> – and support efforts to protect the flower-rich habitats they rely on and enrich, while most of us are tucked up in bed.</p><img src="https://counter.theconversation.com/content/138472/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard Elton Walton received funding from the Norfolk Biodiversity Information and The Clan Trust for fieldwork costs. </span></em></p>New research sheds light on the unsung heroes of pollination.Richard Elton Walton, Postdoctoral Research Associate in Biology, Newcastle UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1371362020-04-28T09:43:03Z2020-04-28T09:43:03ZWant to help rare birds? Dig a pond<figure><img src="https://images.theconversation.com/files/330329/original/file-20200424-163088-13s3yp5.jpg?ixlib=rb-1.1.0&rect=9%2C0%2C3079%2C2278&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A barn swallow scoops an insect from the pond's surface.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/swallow-bags-bug-barn-high-speed-1423561910">Richard Seeley/Shutterstock</a></span></figcaption></figure><p>The first swallows have made landfall in the UK, fanning out over the greening landscape. The early arrivals, generally males, are a streak of electric blue in the spring sunshine.</p>
<p>These heralds of a new season were once common on the agricultural lowlands of Europe and North America, but many species of farmland bird are in trouble. In the UK, 19 of these species <a href="https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/541593/agindicator-de5-29jul16.pdf">declined by almost half</a> between the 1970s and the late 2000s, as <a href="https://www.rspb.org.uk/our-work/conservation/conservation-and-sustainability/farming/near-you/farmland-bird-declines/">agricultural efforts intensified</a> and vast fields of pesticide-drenched crops replaced a patchwork of meadows, woodland and pasture.</p>
<p>The insects these birds eat <a href="https://theconversation.com/insects-species-that-prefer-crops-prosper-while-majority-decline-114206">have also declined</a>. With fewer habitats and less food, the UK’s turtle dove population has <a href="https://www.bto.org/our-science/publications/state-uks-birds/state-uks-birds-2017">fallen by 98% since 1970</a> while grey partridge numbers are <a href="https://www.gwct.org.uk/research/species/birds/grey-partridge/long-term-trends-in-grey-partridge-abundance/">down by 91% on 1967 levels</a>. Swallow populations are holding up, but <a href="https://app.bto.org/birdtrends/species.jsp?year=2016&s=swall">fluctuate from year to year</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/330835/original/file-20200427-145544-9t7ueu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Changes in farming over the last 50 years have removed much of the food and habitat farmland birds need to thrive.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/aerial-view-summer-grass-silage-fields-1586720899">Juice Flair/Shutterstock</a></span>
</figcaption>
</figure>
<p>John Clare, the farm labourer and poet of the English countryside captured the aerial mastery of <a href="http://johnclare.blogspot.com/2010/04/swallow.html">the swallow in a poem</a>, noting “the horse pond where he dips his wings”. Clare was right to associate this bird with farm ponds. You can still see swallows hawking over them 200 years later, although this has less to do with inspiring poets than getting a good meal. </p>
<p>Ponds are hotspots of insect life in the increasingly barren landscapes of intensive farmland. The adult stages of midges, mayflies and dragonflies hatch from them after a year or two growing as nymphs in the murky depths. When they emerge from the water, they fly up to create what has been called an “<a href="https://www.sciencedirect.com/science/article/pii/S000632071931016X?via%3Dihub">insect chimney</a>” of abundant and particularly nutritious bird food – a beacon for birds to home in on.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ponds-can-absorb-more-carbon-than-woodland-heres-how-they-can-fight-climate-change-in-your-garden-110652">Ponds can absorb more carbon than woodland – here's how they can fight climate change in your garden</a>
</strong>
</em>
</p>
<hr>
<h2>Restoring insect chimneys</h2>
<p>Researchers first discovered these insect chimneys after noticing how farmland bird numbers tended to increase around ponds that had been <a href="https://doi.org/10.1016/j.agee.2018.12.015">restored in north Norfolk</a>. Like many lowland landscapes, the once abundant ponds of Norfolk – dug out for watering livestock, producing fish, washing equipment and a host of day-to-day tasks – are now abandoned, shrouded in impenetrable willow and alder. Restoring the ponds by cutting back the trees and digging out the sludge brings them <a href="https://www.norfolkfwag.co.uk/norfolk-ponds-project/">back to life</a>. </p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S000632071931016X">In the latest study</a>, ecologists compared insects caught from these restored ponds with bugs emerging from abandoned ponds of a similar age and history nearby, using floating net traps.</p>
<p>The differences between the ponds was startling. There were over 18 times more insects emerging from restored ponds compared to those that hadn’t been restored, and the sheer mass of insects hatching from the restored ponds was 25 times greater. Healthy ponds which have the shroud of overgrown vegetation cut back and the sludge dug out rapidly recover the aquatic plants and insect life they lost, producing many more fatter, juicier insects.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-im-bringing-centuries-old-ghost-ponds-back-to-life-80625">Why I'm bringing centuries-old 'ghost ponds' back to life</a>
</strong>
</em>
</p>
<hr>
<p>The insects from restored ponds were mostly mayflies, compared to the true flies (<a href="https://bugguide.net/node/view/55">Diptera</a>) hatching from their gloomy, unrestored neighbours. A juicy mayfly is more of a meal than the average gnat. Either is still likely to be more nutritious than the meagre fare on the surrounding landscape, but aquatic insects have much higher levels of the best fatty acids for <a href="https://doi.org/10.1073/pnas.1603998113">chick health and development</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/330974/original/file-20200428-110738-t8p0n8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Farm ponds can offer a vital food source to struggling bird species.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/farm-pond-33007246">Bkp/Shutterstock</a></span>
</figcaption>
</figure>
<p>Most bird species – 33 of the 36 recorded – were much more numerous at the restored ponds. All three aerial specialists – swallows, house martins and swifts – were only recorded at these sites, probably as they’re unable to hawk through the gloom and tangle of the unrestored ponds. They may also have been tempted there <a href="https://discovery.ucl.ac.uk/id/eprint/10081473/">by tasty pollinator insects</a>, which tend to be lured towards open ponds.</p>
<p>Insects hatching from the different ponds did so at different times, too. So not only do the birds benefit from a chimney of food at each pond, the staggered timings of these chimneys developing creates a seasonal conveyor belt of food. Each pond hits its peak of insects emerging at different times, so food supply can last throughout the season.</p>
<p>Eventually, autumn will come and the swallows, martins and swifts will return south to “cheat the surly winter into spring”, as John Clare once wrote. But beneath the still surface of little ponds, next year’s bird food buffet will be brewing.</p><img src="https://counter.theconversation.com/content/137136/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mike Jeffries 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>Ponds create ‘insect chimneys’ which are a boon for hungry farmland birds.Mike Jeffries, Associate Professor, Ecology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1285192020-01-22T17:10:14Z2020-01-22T17:10:14ZCollapsing permafrost is transforming Arctic lakes, ponds and streams<figure><img src="https://images.theconversation.com/files/311427/original/file-20200122-117958-1e4aclp.JPG?ixlib=rb-1.1.0&rect=376%2C144%2C3396%2C2440&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Some lakes in the Arctic are expanding and others are disappearing as permafrost thaws.
This lake north of Inuvik, N.W.T., is expanding as the ice wedges (darker lines leading away from the lake) around this lake melt and the ground subsides.</span> <span class="attribution"><span class="source">(Philip Marsh)</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Lakes, ponds and streams <a href="https://doi.org/10.5194/essd-9-317-2017">cover a large fraction of the low-lying tundra that circles the Arctic</a>. For example, roughly 65,000 lakes and ponds lie within the <a href="https://doi.org/10.1029/2006WR005139">Mackenzie Delta</a> and an <a href="https://doi.org/10.1002/hyp.7179">area to its east</a>. </p>
<p>Lakes across this terrain often exist because of the impermeable nature of the permafrost around and below these lakes. Some of this permafrost has existed here since the last ice age. </p>
<p>Yet as the climate warms, this permafrost is at risk of thawing for the first time in tens of thousands of years. Permafrost thaw has already caused some of these lakes to drain and dry up, and others to expand. Dramatic changes over the last 70 years have been well documented through air photos and satellite images. </p>
<p>These lakes are linked by a vast network of rivers and streams, and are important habitat for large populations of migratory birds, fish and mammals. They are also vital to the lives of northerners, who use them for hunting, fishing, trapping, transportation, fresh water and recreation.</p>
<p>With <a href="https://doi.org/10.1038/s41561-019-0306-x">increasing evidence of ecosystem destruction around the world</a> related to the changing climate, there is also increasing concern that unique Arctic freshwater ecosystems are under threat.</p>
<h2>Disappearing lakes</h2>
<p>Lakes controlled by the presence of permafrost can drain rapidly if the permafrost gives way, a process called catastrophic lake drainage. Sometimes an entire lake can drain in as little as a day, like the one that we studied after it <a href="https://doi.org/10.1002/hyp.1035">vanished from the landscape north of Inuvik, N.W.T., in 16 hours in August 1989</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307755/original/file-20191218-11919-z17d4c.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">
<figcaption>
<span class="caption">A drained lake basin, with shrubs turning yellow in the fall. This lake in the Trail Valley Creek watershed north of Inuvik, N.W.T., drained in August 1989.</span>
<span class="attribution"><span class="source">(Philip Marsh)</span></span>
</figcaption>
</figure>
<p>The disappearance of this lake occurred as water seeped through cracks that had formed in ice wedges during the previous winter. The relatively warm lake water melted the ice within the permafrost, creating a new outlet channel. </p>
<p>Lake drainage presents a serious safety risk to hunters or fishers who may be downstream. It also destroys freshwater habitat, quickly converting it to land, and expands, or even forms, new stream channels. </p>
<p>Like many impacts of climate change on the Arctic, however, unexpected changes also occur. After our initial studies of draining lakes, we expected to find the number of lakes draining annually across this region would increase as the climate warmed. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=489&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=489&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=489&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=614&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=614&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307757/original/file-20191218-11946-1raqljr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=614&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A stream channel enlarged by a rapid, partial drainage of the lake in the background after ice-rich permafrost thawed.</span>
<span class="attribution"><span class="source">(Philip Marsh)</span></span>
</figcaption>
</figure>
<p>Instead, we found <a href="https://doi.org/10.1002/hyp.7179">lake drainage</a> in this area had decreased by one-third between 1950 and 2000. This decrease is likely due to fewer extremely cold winter days that are needed for ice wedge cracking to occur over the winter. </p>
<p>Yet as warming continues, the upper layer of the soil that thaws each year is expected to get deeper and will likely lead to more lake drainage events. An <a href="http://www.doi.org/10.1126/science.1108142">increase in lake drainage has already been reported in Siberia</a>, and this is likely the long-term future of many Arctic lowland lakes. </p>
<h2>Expanding lakes</h2>
<p>Other lowland lakes are expanding as ice in the lake shoreline melts. New lakes may also appear in the tundra depressions that form as ice-rich permafrost thaws, creating new aquatic habitat. Changes like this have been seen in Siberia, but they haven’t been observed in the Inuvik region yet. </p>
<p>This thawing of ice-rich permafrost, called thermokarst, results in <a href="https://doi.org/10.1002/ppp.641">changes in water chemistry and increases in water clarity</a>. These changes will likely affect aquatic food webs in ways that are still poorly understood.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307756/original/file-20191218-11896-60n4fa.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">Three core sections from the upper metre of permafrost at a site north of Inuvik, N.W.T. White material is ice embedded in the permafrost.</span>
<span class="attribution"><span class="source">(Niels Weiss)</span></span>
</figcaption>
</figure>
<p>The Arctic is warming at two to three times the rate of the global average. But determining where the permafrost will thaw — in what way and how quickly — is a <a href="https://doi.org/10.1139/as-2018-0028">complicated puzzle affected by many factors</a>. </p>
<p>For example, there are an increasing number of shrubs growing on the tundra. This affects the accumulation of blowing snow, and may speed up or slow down the rate of snow melt and shorten or lengthen the number of snow-free days. All of this affects permafrost thaw and freshwater systems. </p>
<h2>Millennia of change ahead</h2>
<p>Scientific organizations, <a href="https://changingclimate.ca/CCCR2019/chapter/5-0">governments</a> and <a href="https://unfccc.int/cop25">international groups</a> around the world have all recently warned of the alarming impacts climate change is having — and will have — on the Arctic. Thawing permafrost is already destabilizing buildings, roads and airstrips, eroding coastlines and releasing more carbon into the atmosphere. </p>
<p>It is critically important to realize that permafrost thaw will not stop once the global climate has stabilized, whether at the Paris Agreement limits of 1.5C or 2C, or at much higher levels. Even if anthropogenic carbon emissions are reduced over the coming decades, the concentration of carbon dioxide in the atmosphere will remain above pre-industrial levels for centuries — and likely millennia. Temperatures will also remain high. </p>
<p>As long as the global average temperature stays above the pre-industrial average, permafrost will continue to thaw, ground ice will melt, the land will subside, lakes and streams and freshwater ecosystems will change dramatically, with devastating effects on the peoples of the Arctic who have used these freshwater systems for generations. </p>
<p>Over the next year, governments will make decisions that will limit the increase in global temperature to below 1.5C or allow global warming to further increase to 2C or more. Our decisions will impact the Arctic and the globe for generations. </p>
<p>[ <em>Deep knowledge, daily.</em> <a href="https://theconversation.com/ca/newsletters?utm_source=TCCA&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/128519/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Philip Marsh receives funding from Canada Research Chair program; Natural Sciences and Engineering Research Council of Canada; Canadian Foundation for Innovation; Global Water Futures; NWT Cumulative Impact Monitoring Program; and Government of the NWT. </span></em></p><p class="fine-print"><em><span>Evan Wilcox receives funding from the W. Garfield Weston Foundation. Evan Wilcox is affiliated with the Permafrost Young Researchers Network. </span></em></p><p class="fine-print"><em><span>Niels Weiss receives funding from Global Water Futures. </span></em></p>Hundreds of thousands of lakes, rivers and streams in the Arctic exist only because of the permafrost that lies beneath them. The warming Arctic threatens to change that.Philip Marsh, Professor and Canada Research Chair in Cold Regions Water Science, Wilfrid Laurier UniversityEvan Wilcox, PhD Candidate, Geography, Wilfrid Laurier UniversityNiels Weiss, Research associate (Permafrost), Wilfrid Laurier UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1106522019-02-01T10:19:31Z2019-02-01T10:19:31ZPonds can absorb more carbon than woodland – here’s how they can fight climate change in your garden<figure><img src="https://images.theconversation.com/files/256636/original/file-20190131-75085-aeuuvx.jpg?ixlib=rb-1.1.0&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/pink-water-lily-lake-goldfish-142067443?src=N7w0h3qGCNdhJ3XzsVwzPQ-1-96">NagyDodo/Shutterstock</a></span></figcaption></figure><p>Ponds are taken for granted. Perhaps it’s because most of us have seen them – and on occasion, fallen into them – and think they’re only good for goldfish. Ponds may be the number one habitat for children’s “<a href="https://www.bbc.com/bitesize/articles/z9fkwmn">minibeast</a>” hunts, but we are supposed to grow out of them in adulthood. </p>
<p>As James Clegg, <a href="https://www.nature.com/articles/170681a0">a 20th-century British naturalist wrote</a>, ponds are </p>
<blockquote>
<p>a field particularly suited to the activities of the amateur, whose humble pond-hunting, if carried out systematically and carefully, may well result in valuable contributions to science.</p>
</blockquote>
<p>But all-too often, ponds are missed out of conservation strategies which are instead fixated on larger lakes and rivers. This is a serious omission – ponds are the <a href="https://link.springer.com/article/10.1007/s10750-015-2554-0">most common and widespread habitat</a> for all plants and animals across the continents and islands of Earth, from Antarctica to the tropics. Perched on the surface of Alpine glaciers or waiting out desert droughts to refill with the rains, deep in equatorial forest or amid the city sprawl. They could well be <a href="https://www.sciencedirect.com/science/article/pii/S0921818102001273">found on Mars</a>. </p>
<p>The past 20 years have seen a blossoming of research into ponds, led in the UK by the <a href="http://www.europeanponds.org/">Freshwater Habitats Trust and, internationally, the European Pond Conservation Network</a>. These organisations bring together researchers and practitioners to help conserve pond biodiversity. Their work has revealed that ponds are biodiversity hotspots in the landscape, disproportionately rich in species when compared to rivers, streams and lakes and <a href="https://link.springer.com/chapter/10.1007/978-90-481-9088-1_2">home to many rare specialists</a>, such as <a href="https://freshwaterhabitats.org.uk/pond-clinic/identifying-creatures-pond/fairy-shrimp/">fairy</a> and <a href="https://www.theguardian.com/environment/2015/may/24/specieswatch-tadpole-shrimp-oldest-living-creature">tadpole shrimps</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=436&fit=crop&dpr=1 600w, https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=436&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=436&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=548&fit=crop&dpr=1 754w, https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=548&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/256634/original/file-20190131-112389-1kwpod0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=548&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tadpole shrimps (<em>Triops cancriformis</em>) are the world’s oldest living animals and live in ponds.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/notostraca-two-tadpole-shrimps-triops-cancriformis-55996426?src=_W05oGa4bjeIqTl6tPC8nA-1-0">Repina Valeriya/Shutterstock</a></span>
</figcaption>
</figure>
<p>Ponds benefit humans by slowing down water run-off that can cause flooding and <a href="https://link.springer.com/article/10.1007/S10750-013-1719-Y">mopping up excess nutrients</a> – a great example of what are now recognised as “<a href="https://www.sciencedirect.com/science/article/pii/S0048969718327268">small water bodies</a>” that enrich and enliven a landscape. But, globally, ponds may also be important in influencing atmospheric carbon by storing and releasing it, given the intensity of geochemical processes and the sheer number of ponds around the world. However, just how fast ponds can bury carbon is poorly understood.</p>
<h2>A carbon sink in your own backyard</h2>
<p>Measuring the rate at which ponds can store carbon is tricky, primarily because the age of many ponds is unknown. To get <a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/fee.1988">precise measurements of carbon burial rates</a> we exploited an unusual opportunity using some small, lowland pools whose age is known to the exact day. The ponds were dug out in 1994, at Hauxley Nature Reserve in north-east England. Their original purpose was to follow the <a href="https://link.springer.com/article/10.1007/s10750-011-0678-4">colonisation of plants and invertebrates</a>.</p>
<p>Two decades later they had accumulated a layer of sediment, dark and rich in organic debris, distinctly different to the underlying clay. We used sediment cores and dug out all of the sediment from some ponds, to measure the organic carbon that had accumulated. The amount of carbon in the cores was scaled up to the amount dug up from other ponds to reflect the total volume of sediment.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/256079/original/file-20190129-108367-wgrd51.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">
<figcaption>
<span class="caption">Ponds are carbon sinks which can fit well in intensively managed landscapes.</span>
<span class="attribution"><span class="source">Mike Jeffries</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The ponds’ burial rates for organic carbon ranged from 79 to 247g per square metre per year, with a mean of 142g. These rates are high – much higher than the rates of 2-5g attributed to surrounding habitats such as <a href="http://digital.csic.es/bitstream/10261/89790/1/Downing-GBC-2008-v22-GB1018.pdf">woodland or grassland</a>. Small ponds occupy a <a href="https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/fee.1988">tiny proportion of the UK’s land area</a> – scarcely 0.0006% – compared to grassland at 36% or 2.3% for ancient woodland. But the rate of carbon burial we found would result in ponds burying half as much as the vastly greater expanse of grassland.</p>
<p>However, the role ponds play in the carbon cycle is complicated. Some ponds may be significant sources of greenhouse gases, such as <a href="https://www.nature.com/articles/s41598-018-27770-x">permafrost thaw ponds</a> in the Arctic which release even more carbon as the tundras they’re found in warm. Our Hauxley ponds can switch back and forth from being a net sink to a net source of carbon as they dry out or re-flood. Nevertheless, our ponds have accumulated plenty of carbon over their 20 years and provided a home to a wealth of animals and plants.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/256078/original/file-20190129-108342-33dvnv.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">
<figcaption>
<span class="caption">Researchers take carbon cores from ponds at Hauxley Nature Reserve.</span>
<span class="attribution"><span class="source">Mike Jeffries</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Nothing was done to engineer carbon burial in our ponds – there was no artificial enhancement of productivity to maximise carbon capture. They are small, shallow, lowland ponds among the intensively farmed landscapes typical of much of the temperate climes. Similar ponds and tiny wetlands are dotted throughout the local landscape, primarily scraped out for wildlife conservation. </p>
<p>These lowland ponds are easy to create, <a href="https://freshwaterhabitats.org.uk/pond-clinic/create-pond/">even in a back garden</a>. They can be small and temporary – clean water is the key – and the value of their wildlife is now firmly understood. No longer overlooked, the importance of ponds in the carbon cycle and in fighting climate change is becoming apparent.</p><img src="https://counter.theconversation.com/content/110652/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mike Jeffries 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>Ponds are good for more than just decorating the garden – they could be your best tool in fighting climate change.Mike Jeffries, Associate Professor, Ecology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/990572018-07-04T14:24:09Z2018-07-04T14:24:09ZMake your garden frog friendly – amphibians are in decline thanks to dry ponds<figure><img src="https://images.theconversation.com/files/226141/original/file-20180704-73303-1gtda3d.jpg?ixlib=rb-1.1.0&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/marsh-frog-rana-ridibunda-single-water-145072183?src=xvavMacb92tEg844472MZg-3-5">Shutterstock</a></span></figcaption></figure><p>Garden frogs and toads are in decline. The latest data from <a href="https://www.rspb.org.uk/about-the-rspb/about-us/media-centre/press-releases/garden-survey-reveals-sightings-of-frog-and-toad-are-drying-up-in-scotland/">RSPB Garden Birdwatch</a> reveals that we are seeing one-third fewer toads and 17% fewer frogs compared to 2014. Many people forget that our gardens can be important havens for wildlife. But with ponds drying up, amphibians are losing out. </p>
<p>We should be worried about these declines. Frogs and toads may not be our most glamorous garden inhabitants, but they offer an important opportunity to connect with wildlife within a domestic environment.</p>
<p>As RSPB conservation scientist Dr Daniel Hayhow <a href="https://www.independent.co.uk/environment/uk-frogs-toads-gardens-ponds-decline-rspb-birdwatch-wildlife-a8409501.html">says</a>: </p>
<blockquote>
<p>Most people remember seeing tadpoles at the local pond or a toad emerging from under a rock while they were growing up. These first experiences with nature stay with us forever. Unfortunately, the sights and sounds of wildlife that were once common to us are sadly becoming more mysterious.</p>
</blockquote>
<p>These early connections with wildlife are being lost, leading to concerns that some children may be suffering from <a href="http://richardlouv.com/books/last-child/">nature deficit disorder</a> which can affect their mood and attention. <a href="http://science.sciencemag.org/content/295/5564/2367.2">Research shows</a> that children are more familiar with Pokémon characters than they are with our native wildlife. We need to find more ways to encourage interactions with nature. Ponds, even small ones, are a great way of doing this. </p>
<p>Population declines in amphibians is caused by the reduction of garden ponds, and the reduced numbers of ponds in the wider countryside. We <a href="https://freshwaterhabitats.org.uk/habitats/pond/">lost 50% of our ponds</a> in the UK over the 20th century, and many that are left are in a poor condition because of pollution and lack of management. </p>
<p>Frogs and toads need clean ponds in which to breed, but outside the breeding season you’ll find them in tall grass and log piles. The fashion of keeping our gardens meticulously neat and tidy is leaving our wildlife with nowhere to hide. Amphibians also provide a very useful pest control service (they love eating slugs and snails) so encouraging them into gardens could bring many benefits. </p>
<p>So how do we help? The Freshwater Habitats Trust is leading the <a href="https://freshwaterhabitats.org.uk/projects/million-ponds/">Million Ponds Project</a> with the aim of creating networks of ponds. You don’t need to rebuild your garden to get involved, as even a small outside tub can be enough to provide a suitable habitat for amphibians. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/RmdxdmlNAFY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>If you are feeling more generous, then creating a larger pond can be a fun project – especially with children. Once put in, it will only take a matter of days before something decides to make it their home. It will usually be invertebrates and plants to begin with, but it won’t take long for it to be found by a nearby frog or toad population. </p>
<h2>Pond life</h2>
<p>Another benefit of gardening with wildlife in mind, is that often it means that you need to do less work. Mowing your lawn less frequently provides a great habitat for wildlife. And creating a log pile, putting up nest boxes for birds or putting in a hole in your fence to allow access for hedgehogs, are all low-effort activities which are highly effective. </p>
<p>There are even ways to get involved if you do not have a garden. You can become a local “<a href="https://www.froglife.org/what-we-do/toads-on-roads/">toad patroller</a>”, helping toads to navigate roads safely as they migrate to their breeding ponds. Or you could become a citizen scientist by reporting whenever you see a frog or toad through <a href="https://www.arc-trust.org/report-your-sightings">Amphibian and Reptile Conservation</a>, and taking part in the <a href="https://www.rspb.org.uk/fun-and-learning/for-families/family-wild-challenge/?utm_source=promotions&utm_campaign=wildchallenge">RSPB’s Wild Challenge</a>. </p>
<p>Gardens in the UK might account for <a href="https://www.bbc.co.uk/news/uk-41901294">less than 2%</a> of our total land use, but <a href="https://www.gov.uk/government/publications/rural-population-and-migration/rural-population-201415">83% of people live in urban areas</a>. Small adjustments in gardens could lead to big changes in frog and toad populations – which would be good news for them, and provide gardeners young and old with a boost at the same time.</p><img src="https://counter.theconversation.com/content/99057/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Becky Thomas 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>As ponds dry up, so too does our connection to nature.Becky Thomas, Senior Teaching Fellow in Ecology, Royal Holloway University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/806252017-07-14T14:19:13Z2017-07-14T14:19:13ZWhy I’m bringing centuries-old ‘ghost ponds’ back to life<figure><img src="https://images.theconversation.com/files/178083/original/file-20170713-12477-t9q3tx.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption"></span> <span class="attribution"><span class="source">Emily Alderton</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Over the past century <a href="http://impactsofclimatechange.info/upload/MF14173.pdf">half of the world’s ponds and wetlands have been destroyed</a>, with many being filled in and turned into agricultural land. However, all is not lost, and it is possible to “resurrect” these buried habitats from the seeds and eggs stored within their historic sediments. A new conservation approach pioneered by the UCL <a href="http://www.geog.ucl.ac.uk/research/research-centres/pond-restoration-research">Pond Restoration Research Group</a> can restore aquatic habitats lost to the landscape for centuries.</p>
<p>Ponds can be extremely biodiverse. They support <a href="https://link.springer.com/chapter/10.1007%2F978-90-481-9088-1_1">more aquatic species</a> than any other freshwater habitat and provide important food sources for farmland <a href="http://www.sciencedirect.com/science/article/pii/S016788091630456X">birds</a> and bats. </p>
<p>At the start of the 20th century there were an estimated 800,000 ponds in England and Wales – now, it is thought that <a href="http://www.countrysidesurvey.org.uk/content/ponds-report-2007">fewer than a quarter</a> of these remain. Similar levels of pond loss have occurred across farmland in <a href="https://www.researchgate.net/publication/225247396_Dynamics_of_small_biotopes_in_Danish_agricultural_landscapes">Europe</a> and <a href="https://www.fws.gov/wetlands/Documents/Status-and-Trends-of-Prairie-Wetlands-in-the-United-States-1997-to-2009.pdf">North America</a>, associated with increasing intensification of agriculture. Pond and hedgerow loss are often linked as hedges are uprooted and used to fill in ponds, before ploughing over the entire area. </p>
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<a href="https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=341&fit=crop&dpr=1 600w, https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=341&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=341&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=428&fit=crop&dpr=1 754w, https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=428&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/178085/original/file-20170713-12241-10mpbod.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=428&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 ghost pond in north Norfolk prior to resurrection.</span>
<span class="attribution"><span class="source">Emily Alderton</span>, <span class="license">Author provided</span></span>
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<p>Many lost ponds leave behind a “ghostly” mark in the landscape – visible as damp depressions, areas of poor crop cover, or changes in soil colour. Colleagues and I have recently discovered that these buried “ghost ponds” are not completely lost, but can be resurrected from historic seeds lying dormant underneath intensively cultivated agricultural fields. </p>
<p>These ghosts are an abundant yet overlooked conservation resource. Resurrecting them would of course mean more ponds, which in turn links up aquatic landscapes as plants and animals jump from pond to pond and species are able to thrive in larger populations. But the main advantage of a ghost pond, compared to a new pond, is the historic seed bank buried below the surface. This provides a source of local native species, speeding up the process of colonisation, and potentially restoring lost populations or even locally extinct species to the resurrected pond.</p>
<p>We already knew that aquatic seeds were able to survive dormant for centuries within existing lakes and wetlands. Scientists recently tested 13 lakes in Russia, for instance, and found stoneworts (a keystone species in aquatic habitats), could grow from <a href="https://www.researchgate.net/publication/264709438_Long-lived_banks_of_oospores_in_lake_sediments_from_the_Trans-Urals_Russia_indicated_by_germination_in_over_300_years_old_radiocarbon_dated_sediments">300 year-old spores</a> collected from lake sediments. </p>
<p>However, our recent paper, published in the journal <a href="http://www.sciencedirect.com/science/article/pii/S0006320717304342">Biological Conservation</a>, is the first to demonstrate this astonishing survival ability within habitats which had been assumed lost to agriculture. In our study, we resurrected <a href="https://ghostponds.wordpress.com/">three ghost ponds in north Norfolk</a>, eastern England. These ponds were similar in type, location and surrounding land use to the <a href="http://www.sciencedirect.com/science/article/pii/S0006320717304342">8,000-plus ghost ponds buried across Norfolk</a> and many more across the UK. While buried, ghost ponds are subject to the typical stresses of intensive agriculture (soil compaction, fertiliser and herbicide use), making the long-term survival of their aquatic seed banks particularly astonishing.</p>
<p>Our three study ponds had been buried for around 45, 50 and 150 years. Each was re-excavated down to the pond’s historic level, which was easily distinguished from the overlying topsoil by its dark colour, silty texture, and even its distinctive “pond smell”. This layer of sediment was left mostly undisturbed to provide the source of historic seeds and eggs within each pond.</p>
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<figcaption>
<span class="caption">The ‘resurrection’ of a ghost pond; a) First, a trench is dug to locate the historic pond b) aquatic and wetland plant seeds found in the historic sediment then rapidly colonise the pond c) one year after ‘resurrection’</span>
<span class="attribution"><span class="source">Emily Alderton</span>, <span class="license">Author provided</span></span>
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<p>All three ghost ponds were colonised within six months by native plant species. In total, 12 species of aquatic plant colonised the ghost ponds and eight of these species proved to have originated from the seeds that had lain dormant below the ground. To check these plants really had grown from the ghostly remains of the previous pond, and hadn’t been carried in by the wind or seed-eating birds, we kept some of the historic sediment in sealed aquariums. There, even under controlled conditions, the same species still grew out of this centuries-old sediment.</p>
<p>Species recolonising from the historic seed bank included stoneworts, which are <a href="https://www.researchgate.net/publication/270650472_The_role_of_charophytes_Charales_in_past_and_present_environments_An_overview">important for maintaining water quality</a> but are increasingly threatened in farmland, and floating leaved pondweeds, which provide <a href="https://www.researchgate.net/publication/229055928_Identifying_high-quality_pond_habitats_for_Odonata_in_lowland_England_Implications_for_agri-environment_schemes">key habitat for dragonflies and damselflies</a>. We also found crustaceans including Daphnia (water fleas), and copepods (tiny invertebrates which swim in a jumpy motion using their antennae), were able to hatch from eggs buried in the ghost pond sediment samples.</p>
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<figcaption>
<span class="caption">a & b) Stoneworts and broad leaved pondweed growing from 50-year old sediment c) A germinating rush seed, sieved from 150-year old sediment.</span>
<span class="attribution"><span class="source">Emily Alderton</span>, <span class="license">Author provided</span></span>
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<p>Although only common species were resurrected from the sediments of our three ghost ponds, these included seeds of all different sizes and types – from a variety of aquatic plant species. This suggests that a wide range of plants, including potentially rare or even <a href="http://www.sciencedirect.com/science/article/pii/S030437701400117X">locally extinct species</a>, could potentially survive within the buried sediments of ghost ponds. The boost to recolonisation speed and diversity from the historic seed and egg bank may also reduce the risk of invasive species becoming established.</p>
<p>Ghost ponds represent abundant yet overlooked biological time capsules. Their restoration could facilitate the rapid return of wetland habitats and aquatic plants into the agricultural landscape. This process could play a significant role in reversing some of the habitat and biodiversity losses caused by the global disappearance of agricultural wetlands – and I urge conservationists to make use of this valuable yet hitherto little considered resource.</p><img src="https://counter.theconversation.com/content/80625/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emily Alderton receives funding from Natural Environment Research Council (NERC)</span></em></p>Pond life can recolonise from seeds and eggs which lie dormant in the soil.Emily Alderton, PhD student in Aquatic Ecology, UCLLicensed as Creative Commons – attribution, no derivatives.