tag:theconversation.com,2011:/fr/topics/urban-ecology-20404/articlesUrban ecology – The Conversation2024-03-14T12:43:43Ztag:theconversation.com,2011:article/2196872024-03-14T12:43:43Z2024-03-14T12:43:43ZCity mouse or country mouse? I collect mice from Philly homes to study how they got so good at urban living<figure><img src="https://images.theconversation.com/files/576250/original/file-20240216-24-90lbyl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">European colonizers brought mice to the Americas, where they squeaked out a comfortable life.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/mouse-peeking-out-of-the-hole-royalty-free-image/525023427">Dejan Kolar/iStock Collection via Getty Images Plus</a></span></figcaption></figure><p>Dusty barns, gleaming stables and damp basements. These are all places where you might find a house mouse – or a member of my research team. </p>
<p>I’m an <a href="https://scholar.google.com/citations?user=DMxMLmwAAAAJ&hl=en">evolutionary biologist</a>, and my lab at Drexel University studies wild house mice. With help from Philly residents, we are collecting mice from high-rises and row homes to learn more about the impacts of city living on house mice. In short, we want to know whether there is any scientific basis to <a href="https://sites.pitt.edu/%7Edash/type0112.html#aesop">“The Town Mouse and the Country Mouse” fable</a> in which the cousins eat differently based on where they live.</p>
<p><a href="https://www.npr.org/2023/07/26/1190071137/its-hot-out-there-a-new-analysis-shows-its-much-worse-if-youre-in-a-city">Cities are hotter</a> and they have a lot of people living in high densities, which means more trash and usually more pollution. This can affect how <a href="https://www.doi.org/10.1126/science.aam8327">species that live in cities evolve</a>. Cities are also dominated by artificial habitats such as sidewalks, high-rises and subways rather than open fields and forests. </p>
<p>We are interested in many possible changes, but especially in whether the many differences between urban and rural environments translate into genetic differences between city mice and country mice, such as which versions of genes related to metabolism are more common. </p>
<p>To find the answers, we sequence the mice’s genomes. With that data, we can answer a variety of questions, such as: Are city mice more or less genetically diverse than country mice? Are there regions of DNA, the molecule that encodes genetic information, that are consistently different between urban and rural mice? If so, what are the functions of genes in those regions? </p>
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<span class="caption">Just how different are city mice and country mice? Researchers are studying their guts and genes to find out.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Rackham_town_mouse_and_country_mouse.jpg">Arthur Rackham, public domain via Wikimedia Commons</a></span>
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<h2>Why study house mice?</h2>
<p>One reason we study house mice is because they are so widespread. European colonizers <a href="https://doi.org/10.1093/g3journal/jkac332">brought house mice to the Americas</a> around 500 years ago. The rodents have now spread into many different climates and habitats across North and South America in most places that humans live, including Philadelphia. </p>
<p>Though small in size, house mice have made immeasurable <a href="https://shop.elsevier.com/books/the-mouse-in-biomedical-research/fox/978-0-12-369456-0">contributions to genetics and medicine</a>. They are mammals like humans, but house mice reproduce quickly and are relatively easy to breed and maintain. In fact, part of why scientists adopted mice early on as a model system is because people were already breeding “<a href="https://doi.org/10.7554/eLife.05959">fancy mice</a>” as pets. As a result, methods for keeping and breeding them were known.</p>
<p>Mice have many visible traits for geneticists to study. My team wants to know more about the genes and traits that have contributed to their ability to thrive in a variety of environments. The work we do with wild house mice also feeds back into work with laboratory mice and biomedical research. The house mice found in attics and cabinets are the same species that are studied in labs, but they are <a href="http://doi.org/10.1038/ng.847">more genetically diverse</a> than laboratory strains. Our project will generate whole genome sequences from many wild mice, and that data can help scientists who study traits and diseases. </p>
<h2>Tips for catching mice</h2>
<p>I previously worked on a large project studying <a href="https://doi.org/10.1371/journal.pgen.1007672">how house mice have adapted to different climates</a> in the Americas. For that project, I went to many, many farms throughout the eastern United States and became very good at catching mice in barns. </p>
<p>Starting this project with a focus on cities was a new challenge. First, our team had to find Philly residents who wanted us to trap their mice. We spent a lot of time spreading the word on social media, talking to friends and posting flyers. </p>
<p>We talked to many Philadelphians who were frustrated with trying to rid their homes of mice. Some had videos of house mice avoiding the traps they had set or stealing the bait and running away. We share this frustration and feel it keenly. In some cases, it took us many days to catch a single mouse in an apartment.</p>
<p>Part of the reason is because many Philadelphia houses are old. This means they are often full of character – and holes that give mice great places to hide. Luring the mice out of their nests and into our traps is difficult. We had the most success with peanut butter bait, which has a strong and very appealing odor for mice. But mice are omnivores, eating a diverse diet that includes insects. We have heard many stories from community members who used bait such as chocolate, cereal, cookies and even bacon bits. </p>
<h2>What’s next</h2>
<p>We hope to start sharing results over the next two years. We are working in three cities – Philadelphia, New York City and Richmond, Virginia – and have completed our first collections. Now we need to generate and analyze genetic data, so we are very busy in the lab. </p>
<p>We are extracting DNA, as well as another form of genetic material called RNA, from different tissues. With the DNA we will study how much genetic variation exists within city mouse populations, and whether there are genetic differences between urban and rural mice. The RNA will help us understand how differences in DNA translate into differences in metabolism, physiology and other cellular processes. </p>
<p>We will also look to see whether there are differences in traits. For example, we will measure their skulls and skeletons. We will sequence the DNA of the microbes in their digestive system to learn about their gut microbiomes, the collection of bacteria that live in their digestive system, and use <a href="https://www.futurelearn.com/info/courses/archaeology/0/steps/15267">stable isotope analysis</a> to identify any differences in their diets. Stable isotope analysis of diet uses the ratios of naturally occurring atoms of elements such as carbon and nitrogen to determine what types of food an organism has eaten.</p>
<p>Cities are full of wildlife. Learning about how cities shape the evolution of mice may help us find better ways to manage mouse populations and other urban wildlife while also better understanding evolution.</p><img src="https://counter.theconversation.com/content/219687/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Megan Phifer-Rixey receives funding from the National Science Foundation (NSF CAREER 2332998 Division of Environmental Biology).
</span></em></p>An evolutionary biologist is studying what these resilient urban pests can teach us about adaptation and evolution.Megan Phifer-Rixey, Assistant Professor of Biology, Drexel UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2170822023-12-07T19:19:04Z2023-12-07T19:19:04ZWe thought we’d find 200 species living in our house and yard. We were very wrong<figure><img src="https://images.theconversation.com/files/559530/original/file-20231115-19-q1g80l.jpeg?ixlib=rb-1.1.0&rect=0%2C42%2C4025%2C2685&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dot-underwing moth (_Eudocima materna_) found in the researchers' yard.</span> <span class="attribution"><span class="source">Matthew Holden</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>We are biodiversity researchers – an ecologist, a mathematician and a taxonomist – who were locked down together during the COVID pandemic. Being restricted to the house, it didn’t take long before we began to wonder how many species of plants and animals we were sharing the space with. So we set to work counting them all.</p>
<p>We guessed we would find around 200–300, and many of our colleagues guessed the same. </p>
<p>There was nothing extraordinary about our 400 square metre block of land in Annerley, a suburb of Brisbane in Queensland, Australia. Roughly half the block was occupied by a three-bedroom house.</p>
<p>What was extraordinary was the number of species we discovered there. As revealed in our just-published study, starting on the first day of lockdown and continuing over the course of a year, we catalogued <a href="https://doi.org/10.1002/ecy.4225">1,150 species</a> on our inner-city property.</p>
<h2>Familiar faces and rare recluses</h2>
<p>Many of the species were what any east coast suburban Australian would expect: ibises, brush turkeys, kookaburras, possums and flying foxes. But, surprisingly, others had rarely been recorded. </p>
<p>In fact, three of the 1,150 species had never been documented in Australia’s leading biodiversity database at that point. This included a rare mosquito, a sandfly and an <a href="https://en.wikipedia.org/wiki/Platydemus_manokwari">invasive flatworm</a> that can cause populations of native snails to decline. </p>
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Read more:
<a href="https://theconversation.com/the-39-endangered-species-in-melbourne-sydney-adelaide-and-other-australian-cities-114741">The 39 endangered species in Melbourne, Sydney, Adelaide and other Australian cities</a>
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<p>We found common foes, but also many friends. That rare mosquito was just one of 13 mosquito species we found. The cupboards accommodated pantry moths and grain weevils, but also spiders to prey on them (we recorded 56 species). </p>
<p>Our lack of assiduous garden-tending meant weeds were prolific; of the 103 plant species we documented on the property, 100 were non-native. </p>
<p>Apart from weeds, however, the vast majority of species were actually native. Our two massive lilly-pilly trees provided shade, shelter and food, magnets for numerous pollinators and other species. </p>
<h2>Bees and butterflies</h2>
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<a href="https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photo of sleeping bees hanging on a plant stem." src="https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=889&fit=crop&dpr=1 600w, https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=889&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=889&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1117&fit=crop&dpr=1 754w, https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1117&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/560107/original/file-20231117-27-3o9y36.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1117&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">Blue-banded bees sleep grasping plant stems with their mandibles.</span>
<span class="attribution"><span class="source">Andrew Rogers</span></span>
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<p>The yard was filled with pollinators. For example, there were hoverflies which, at a quick glance, you’d think were wasps. We had ten species of those, a fraction of the more than 109 species of flies we found. </p>
<p>Native blue-banded bees and fluffy teddybear bees roosted in the hedges under our windows at night. They were just two of more than 70 bee and wasp species we observed. </p>
<p>We also counted a mindblowing 436 species of butterflies and moths. A few were as large as a human hand, but most were tiny and barely noticeable. Some were brightly coloured, while others – like the vampire moth <em>Calyptra minuticornis</em> – seemed boring until we began to study their behaviour. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1252048652337479681"}"></div></p>
<p>The moth <em>Scatochresis innumera</em> is another interesting one: as a caterpillar, it lives inside a single possum poop before emerging as an adult. </p>
<p>The caterpillars of <em>Parilyrgis concolor</em>, yet another moth, live in spiderwebs, surviving on the spider’s food waste, while the adults can be found hanging bat-like from the spiderwebs. It is not known how they avoid getting eaten by the spiders.</p>
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<img alt="A photo of a brown moth hanging from a spiderweb." src="https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=423&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=423&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=423&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=532&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=532&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564100/original/file-20231207-27-e6h1m6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=532&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The caterpillars of the moth Parilyrgis concolor live in spiderwebs, and adults often hang from webs like bats.</span>
<span class="attribution"><span class="source">Russell Yong</span></span>
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<h2>Wasps and beetles</h2>
<p>We recorded ten species of lycaenid “blue” butterflies, many of which use ants to protect their caterpillars from predators, including certain wasp species which would lay eggs in them if they got a chance.</p>
<p>These wasps are called parasitoids – meaning their young develop in other organisms, eventually killing them. Some of these wasps even parasitise other parasitoid wasps. Our urban homes are clearly complex ecosystems.</p>
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<a href="https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photo of a small orange and black bug on a thin tree branch." src="https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=659&fit=crop&dpr=1 600w, https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=659&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=659&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=828&fit=crop&dpr=1 754w, https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=828&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/560183/original/file-20231117-19-6mz01y.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=828&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A tiny Braconid wasp that parasitises other insects.</span>
<span class="attribution"><span class="source">Matthew Holden</span></span>
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<p>We were surprised to only find just under 100 beetle species (the fourth most common group of organisms in our study). Beetles are widely believed to be the most diverse order of insects on the planet. </p>
<p>Our finding may be a sign of declining beetle populations, which has been observed around the world. On the other hand, it may just have been a bad year for beetles in our neighbourhood.</p>
<h2>An urban environment teeming with life</h2>
<p>Overall, we found far more species than we expected, and we showed that even urban environments can be teeming with wildlife. </p>
<p>A big reason for that was surely the vegetation: the shrubs, trees and weeds in the yard. The monotony of perfectly tended lawn and heavily sprayed and manicured flowerbeds may be nice to look at and for the kids to play on but, as habitat for urban wildlife, it is lacking. </p>
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Read more:
<a href="https://theconversation.com/heres-how-to-design-cities-where-people-and-nature-can-both-flourish-102849">Here's how to design cities where people and nature can both flourish</a>
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<p>Our own laziness meant we did little work in the garden. However, by giving the mower and pesticides a break, and by sacrificing some lawn for native trees, shrubs and flowering weeds, we ended up with something much more valuable.</p>
<p>But no matter what you do to maintain your home, definitely check your porch or balcony light tonight, and keep your eye out for urban wildlife around your home. You too can experience some pretty amazing nature, no matter how urban the environment you live in.</p><img src="https://counter.theconversation.com/content/217082/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew H. Holden receives funding from the Australian Research Council and the Department of Environment and Science, Queensland</span></em></p><p class="fine-print"><em><span>Andrew Rogers and Russell Q-Y Yong 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>An ecologist, a mathematician and a taxonomist were locked down together in a suburban house. So they counted all the species of plants and animals they could find.Matthew H. Holden, Lecturer, School of Mathematics and Physics, The University of QueenslandAndrew Rogers, PhD student, The University of QueenslandRussell Q-Y Yong, PhD candidate, Marine Parasitology, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1940312023-02-27T17:22:54Z2023-02-27T17:22:54ZPlant and animal species that adapt quickly to city life are more likely to survive<figure><img src="https://images.theconversation.com/files/512056/original/file-20230223-2271-9vv3ym.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5982%2C3997&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A global study of urban clover reveals that it is adapting quickly to city life.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/plant-and-animal-species-that-adapt-quickly-to-city-life-are-more-likely-to-survive" width="100%" height="400"></iframe>
<p>It’s five o'clock on a summer morning in Winnipeg. Our research team is unloading a series of small traps from the trunk of our car, which is parked on a residential road. Using a stick, we slather peanut butter from a huge jar into each trap as bait and quietly sneak into the yards we’ve been given permission to enter, placing the traps in suitable locations. </p>
<p>A dogwalker gives us a suspicious glance as they walk by. Traps now set and open, we wait. This effort is to investigate how animals respond to urbanization and <a href="https://doi.org/10.1002/ecs2.3918">what traits enable them to colonize and persist in cities</a>.</p>
<h2>Urban nature</h2>
<p>Urban ecology and evolution are still relatively new fields of study — for a long time, researchers preferred to study nature in remote locations farther away from human influence. But a growing number of scientists are now studying the <a href="https://doi.org/10.1126/science.aaf3630">ecology</a> and <a href="https://doi.org/10.1126/science.aam8327">evolution</a> of animals and plants found in our own backyards, reflecting a realization that cities are important ecosystems where plants, animals, humans and other organisms coexist. </p>
<p>Yet these cities are challenging places for wildlife and plants. Cities are <a href="https://doi.org/10.1002/joc.2201">hot</a>, <a href="https://theconversation.com/urban-noise-pollution-is-worst-in-poor-and-minority-neighborhoods-and-segregated-cities-81888">noisy</a> and <a href="https://theconversation.com/toxic-cities-urban-wildlife-affected-by-exposure-to-pollutants-127590">polluted</a>. The numerous buildings, cars, pets and, of course, people going about their business <a href="http://dx.doi.org/10.5751/ACE-00581-080211">pose many dangers</a> to the species that increasingly share our living quarters. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a red squirrel perched in an eavestrough" src="https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512060/original/file-20230223-24-2iu9g0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Studying red squirrel populations in urban neighbourhoods can show how they have evolved different behaviours to adapt to city life.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>The remaining natural vegetation is also altered in cities. For example, interest in <a href="https://doi.org/10.1016/j.landurbplan.2019.103730">gardening has introduced many new plants and trees to cities</a> that aren’t found in nearby natural areas. These complex and intertwining environmental modifications can make finding food, a suitable mate or a safe shelter challenging for most animals, and make it difficult for native species of plants to thrive in cities.</p>
<h2>What does it take to thrive?</h2>
<p>So, what enables some species to succeed in city living, where other species fail? One of the most important qualities in urban animals is their ability to change their behaviour, coming up with innovative ways to socialize, avoid dangers or cope with challenging urban environmental conditions. </p>
<p>For example, <a href="https://doi.org/10.1163/1568539X-bja10122">mountain chickadees that nest in cities are bolder than their rural counterparts</a> in Kamloops, B.C. Urban coyotes <a href="https://doi.org/10.1093/beheco/arv102">avoid humans (and particularly their cars) by being more active at night</a> in Edmonton. And <a href="https://doi.org/10.1098/rsbl.2020.0813">rosy-faced lovebirds use air-conditioning vents</a> to cool off on hot days in Phoenix, Ariz. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-coyotes-and-humans-can-learn-to-coexist-in-cities-147738">How coyotes and humans can learn to coexist in cities</a>
</strong>
</em>
</p>
<hr>
<p>We also see evidence of rapid evolution in cities, where the genetic material of a population is changing. Urban water fleas, for example, <a href="https://doi.org/10.1111/1365-2435.13184">grow and mature faster</a> and can <a href="https://doi.org/10.1111/gcb.13784">withstand higher temperatures</a> than rural water fleas. Anolis lizards in Puerto Rico have <a href="https://doi.org/10.1111/evo.12925">evolved longer limbs and more toe lamellae — fine scales on the bottom of their feet — in cities</a>, traits that may help individuals better cling to smooth urban surfaces like glass, metal or painted concrete.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a brown lizard perched on a rusted rod" src="https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/512059/original/file-20230223-16-cx42uf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Anolis lizards living in urban areas in Puerto Rico have evolved longer limbs.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Urban clover</h2>
<p>Recently, researchers wanted to know just how widespread these kinds of rapid evolutionary changes are across our cities. <a href="https://www.globalurbanevolution.com/">A global team of researchers</a> — led by University of Toronto scientists and including team members from both my former University of Manitoba lab, and my <a href="https://www.concordia.ca/news/stories/2022/04/20/cities-are-driving-evolutionary-change-in-the-cosmopolitan-white-clover-a-new-global-study-finds.html">department at Concordia University</a> — teamed up to answer this question using the humble clover plant. </p>
<p>The Global Urban Evolution project (or GLUE) underscores <a href="https://knowablemagazine.org/article/living-world/2022/urban-evolution-species-adapt-survive-cities">the important role of cities as testbeds</a> to advance our understanding of the natural world, and evolutionary ecology in particular.</p>
<p>Clover is ubiquitous in cities across the world so researchers visited parks, lawns and roadsides to collect samples from 160 cities and surrounding areas on five continents (gathering a few more suspicious glances from dogwalkers along the way). Considered among “<a href="http://ikee.lib.auth.gr/record/300591?ln=en">the best replicated test of parallel evolution, on the largest scale ever attempted</a>,” results suggest clover populations are indeed <a href="https://doi.org/10.1126/science.abk0989">adapting to urban environments worldwide</a>. </p>
<p>As the GLUE project shows, research undertaken in cities <a href="https://doi.org/10.1016/j.tree.2022.07.012">can help us better understand basic ecological and evolutionary processes and mechanisms</a>. This knowledge can also help us protect declining species, which is critical as we face the dual challenges of biodiversity loss and climate change. </p>
<p>If urban species are evolving, and seemingly before our very eyes, that means <a href="https://urbanevolution-litc.com/2020/05/19/conserving-urban-biodiversity-needs-an-evolutionary-mindset/">biodiversity conservation and management goals are moving targets</a>. Understanding how species are changing over time can help us to better plan and manage for greener, more biodiverse cities. This, in turn, has important implications for the well-being of the 55 per cent of the world’s human population who call an urban area home.</p>
<h2>Studying an urbanizing world</h2>
<p>Back in Winnipeg, a trap in a nearby yard is rattling. A tiny red squirrel has found the peanut butter breakfast and is now full — and also stuck. It’s time for me to get to work. I weigh and measure the squirrel, and then mark it for future identification. Ultimately, this work will tell us how squirrels alter their activity in cities, for example by waking up earlier compared to squirrels in more natural areas, <a href="https://doi.org/10.1098/rspb.2013.0593">as has been found for urban birds</a>. </p>
<p>So, the next time you notice someone catching squirrels in your neighbourhood, collecting clover on lawns or water fleas in city ponds, you might just be witnessing an urban evolutionary ecologist hard at work, trying to discover just what makes their favourite species successful at city living.</p><img src="https://counter.theconversation.com/content/194031/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Riikka Kinnunen's PhD work was supported by a Natural Sciences and Engineering Research Council of Canada Discovery Grant and the University of Manitoba Graduate Fellowship and University of Manitoba Graduate Enhancement of Tri-Council Stipends funding grant. </span></em></p><p class="fine-print"><em><span>Carly Ziter receives funding from the Natural Sciences and Engineering Research Council of Canada, The Social Sciences and Humanities Research Council of Canada, The Fonds de recherche du Québec – Nature et technologies, and Concordia University</span></em></p>Animals and plants living in cities are more likely to thrive when they are able to quickly adapt to urban conditions.Riikka Kinnunen, Postdoctoral research fellow, Biology, Concordia UniversityCarly Ziter, Associate professor, Biology, Concordia UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1868932022-08-03T12:10:42Z2022-08-03T12:10:42ZCoyotes are here to stay in North American cities – here’s how to appreciate them from a distance<figure><img src="https://images.theconversation.com/files/476377/original/file-20220727-15-49bdtr.jpg?ixlib=rb-1.1.0&rect=42%2C0%2C4752%2C3151&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A coyote on a golf course in Scottsdale, Ariz., June 19, 2011.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/9UXnkz">Dru Bloomfield/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Coyotes have become <a href="https://doi.org/10.3897/zookeys.759.15149">practically ubiquitous</a> across the lower 48 United States, and they’re increasingly turning up in cities. The draws are <a href="https://urbancoyoteresearch.com/sites/default/files/resources/ecologycoyotes.pdf">abundant food and green space</a> in urban areas. </p>
<p>At first these appearances were novelties, like the hot summer day in 2007 when a coyote wandered <a href="https://abcnews.go.com/US/story?id=3005523&page=1">into a Chicago Quiznos</a> sub shop and jumped into the beverage cooler. Within a few years, however, coyote sightings became common in <a href="https://narratively.com/tracking-the-great-coyote-invasion-of-nyc/">the Bronx and Manhattan</a>. In 2021 a coyote strolled into a <a href="https://www.usatoday.com/story/news/nation/2021/08/22/coyote-in-classroom-los-angeles-back-to-school/8235396002/">Los Angeles Catholic school</a> classroom. They’re also appearing in <a href="https://www.theglobeandmail.com/canada/article-more-coyotes-are-adapting-to-urban-areas-in-canada-heres-why-they/">Canadian cities</a>.</p>
<p>People often <a href="https://www.rmotoday.com/local-news/study-investigates-fear-of-coyotes-1567946">fear for their own safety</a>, or for their <a href="https://www.wkyc.com/article/news/local/verify/verify-how-likely-is-a-coyote-to-attack-a-small-child-in-northeast-ohio/95-522589979">children</a> or <a href="https://thebark.com/content/are-you-afraid-coyotes">pets</a>, when they learn about coyotes in their neighborhoods. But as an <a href="https://naturalresources.extension.wisc.edu/uw-urban-canid-project/">interdisciplinary team</a> studying how people and coyotes interact in urban areas, we know that peaceful coexistence is possible – and that these creatures actually bring some benefits to cities. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1327368343813197824"}"></div></p>
<h2>Adaptable animals</h2>
<p>Coyotes can <a href="https://urbancoyoteresearch.com/sites/default/files/resources/Urban%20coyote%20ecology%20journal.pdf">thrive in urban environments</a> because they are incredibly adaptable. As omnivores, coyotes can <a href="https://doi.org/10.1111/j.1600-0587.2001.tb00205.x">change their diets</a> depending on <a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1693&context=icwdm_usdanwrc">the type of food that’s available</a>. </p>
<p>In rural areas coyotes may feed on bird eggs, rabbits, deer and a wide range of nonanimal matter, like plants and fruits. In urban environments they’ll supplement their natural diet with human-provided food sources, such as outdoor pet feeders and garbage cans.</p>
<p>Coyotes prefer to live in packs, and usually do so in rural areas. In urban areas, coyotes live in packs as well, although it may not seem that way because they are often seen individually rather than as a group.</p>
<p>Solitary coyotes not associated with a pack are somewhat common but tend to be transitory animals looking to join a pack or establish a new one in an unoccupied territory. These solitary coyotes can roam many miles per day, which enables them to disperse to new cities in search of food. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of the west side of Madison, Wisconsin, with stars indicating places a coyote stopped" src="https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=582&fit=crop&dpr=1 754w, https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=582&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/477210/original/file-20220802-24-q9c9pb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=582&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Urban coyotes can roam multiple miles a day. This map of the west side of Madison, Wisconsin, tracks a male coyote collared by the UW Urban Canid Project. Each red star shows somewhere he stopped over the span of a few days.</span>
<span class="attribution"><a class="source" href="https://www.facebook.com/uwurbancanidproject/photos/a.1581580038745965/3131229720447648/?type=3">University of Wisconsin Urban Canid Project</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Some wild species need very specific types of habitat to survive. For example, the Kirtland’s warbler is a rare North American songbird that breeds only in <a href="https://www.allaboutbirds.org/guide/Kirtlands_Warbler/overview">young jack pine forests in Michigan, Wisconsin and Ontario</a>. In contrast, coyotes are <a href="https://www.worldcat.org/title/wild-canids-their-systematics-behavioral-ecology-and-evolution/oclc/1093505">habitat generalists</a> that can live on and around a wide variety of land types and covers. </p>
<p>Many kinds of habitat that <a href="https://doi.org/10.3996/062013-JFWM-040">coyotes use in rural areas</a>, such as parks, prairies, forest patches and wetlands, are also found in cities. Typically coyotes avoid the urban cores, but <a href="https://urbancoyoteresearch.com/sites/default/files/resources/Urban%20coyote%20ecology%20journal.pdf">in Chicago</a> they inhabit the downtown area and have been able to survive quite well.</p>
<p>Finally, urban coyotes have <a href="https://doi.org/10.5070/V425110351">flexible activity patterns</a>. Most urban coyotes are active mainly between dusk and dawn, when they are less visible than in daylight. However, as coyotes grow used to humans and begin to lose their fear of people, they may be seen more frequently during daylight hours.</p>
<h2>Hunting rodents and spreading seeds</h2>
<p>Studies show that urban coyotes generally avoid direct interactions with people. A long-term <a href="https://digitalcommons.lmu.edu/cate/vol4/iss1/3/">study in Chicago</a> found that these animals are good at adapting to human-built environments and navigating urban areas without being seen by humans. Often people may not realize they’re sharing the urban landscape with coyotes until they see one in their neighborhood. </p>
<p>Despite their <a href="https://www.britannica.com/topic/Coyote-mythology">trickster portrayal in folklore</a> and <a href="https://www.youtube.com/watch?v=0HQeJESRcDU">popular media</a>, coyotes tend to avoid conflict. They enter urban landscapes because they’re opportunistic. And because cities don’t have <a href="https://www.merriam-webster.com/dictionary/apex%20predator">apex predators</a> like wolves or bears, there are lots of smaller wild prey species, such as squirrels and rabbits, running around for coyotes to feed on. </p>
<p>A 2021 study conducted in Madison, Wisconsin, found that the vast majority of human interactions with coyotes there <a href="http://dx.doi.org/doi:%2010.1093/jue/juaa032">were benign</a>. When asked to rank how aggressive coyotes had been during interactions on a scale of 0 (calm) to 5 (aggressive), most of the 398 people in the study chose zero. More than half of the coyotes in the study moved away from the human, indicating that the animals maintained a healthy fear of people.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic explaining how to behave around urban coyotes" src="https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/476380/original/file-20220727-11-fg0yin.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Coyotes are present throughout Florida, including in urban areas like Miami and Tampa-St. Petersburg.</span>
<span class="attribution"><a class="source" href="https://myfwc.com/media/15892/coyotes-in-florida-infographic.jpg">Florida Fish and Wildlife Conservation Commission</a></span>
</figcaption>
</figure>
<p>And having coyotes around can be useful. In urban areas they are at the top of the food chain and can help regulate populations of prey species such as rabbits, rats and mice. Since coyotes are omnivores, they also eat plant material and spread seeds when they defecate. </p>
<p>Our team is working to learn <a href="https://doi.org/10.1080/10871209.2020.1748768">how people feel</a> about coyotes in their urban communities so that we can identify the best ways to foster positive human-coyote relationships. In Madison, we’ve found that many people appreciate coyotes and are likely to respond positively to messages that highlight coyotes as a valued part of the urban landscape. </p>
<h2>Don’t be afraid to haze</h2>
<p>If you encounter an urban coyote, it’s OK to enjoy watching it from a safe distance. But then <a href="https://www.humanesociety.org/resources/coyote-hazing">haze it</a> by making noise – for example, yelling and waving your arms to look big. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/JlC8KTDiIRs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">University of Wisconsin wildlife extension specialist David Drake shows how to haze a coyote.</span></figcaption>
</figure>
<p>For animal lovers, this might seem harsh, but it’s extremely important to make sure the coyote doesn’t get too close. This teaches the animal to keep away from people. In the rare cases in which urban coyotes have attacked humans, the animals typically had <a href="https://www.theguardian.com/us-news/2022/may/23/urban-coyotes-us-suburbs-dallas">become habituated to human presence</a> over time.</p>
<p>If you have pets, keep them leashed in public parks and watch them when they’re loose in unfenced yards. <a href="https://doi.org/10.3389/fevo.2021.687504">Keep their food inside as well</a>. To a coyote, a dishful of dog food is an easy free meal, and it may cause coyotes to revisit the area more frequently than they would if human-provided food weren’t accessible. </p>
<p>Based on existing research, we believe urban landscapes have plenty of room for coyotes and humans to <a href="https://naturalresources.extension.wisc.edu/uw-urban-canid-project/coexisting-with-canids/">coexist peacefully</a>. It starts with each species giving the other enough room to go about its business. To learn more about these amazingly adaptable animals, check out the national nonprofit <a href="https://projectcoyote.org/">Project Coyote</a> and the Wisconsin-based <a href="https://naturalresources.extension.wisc.edu/uw-urban-canid-project/">Urban Canid Project</a>.</p><img src="https://counter.theconversation.com/content/186893/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Drake receives funding from a variety of federal and state government agencies, as well as foundations </span></em></p><p class="fine-print"><em><span>Associate Professor, Department of Life Sciences Communication and Division of Extension, University of Wisconsin-Madison</span></em></p><p class="fine-print"><em><span>Mary Magnuson is affiliated with the University of Wisconsin Urban Canid Project. She is an AAAS Mass Media Fellow working with The Conversation for the summer of 2022. </span></em></p>Urban coyotes prey on rodents and spread plant seeds. It’s OK to observe them from a distance, but then you should chase them off.David Drake, Professor of Forest and Wildlife Ecology and Extension Wildlife Specialist, University of Wisconsin-MadisonBret Shaw, Associate Professor of Life Sciences Communication, University of Wisconsin-MadisonMary Magnuson, Master's student in Environment and Resources, University of Wisconsin-MadisonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1716242022-01-17T14:56:53Z2022-01-17T14:56:53ZLegal tools exist to protect South Africa’s city ecosystems: it’s up to councils to use them<figure><img src="https://images.theconversation.com/files/440464/original/file-20220112-23-vp6rwp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Litter after recent looting in Durban, South Africa. The city recently introduced a scheme that looks to protect biodiversity and associated ecosystems.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The world is experiencing an environmental crisis coupled with rapid urbanisation. This affects city ecosystems, which are a combination of the built environment, planned green spaces and natural biodiversity. They include streets, roofs, parks, trees, rivers and other urban features.</p>
<p>Ecosystems provide <a href="https://www.nwf.org/Educational-Resources/Wildlife-Guide/Understanding-Conservation/Ecosystem-Services">services</a> like regulating air, water and soil quality. In cities, their role in regulating the climate is particularly important. Cities are generally warmer <a href="https://weather.com/science/weather-explainers/news/urban-heat-island-cities-warmer-suburbs-cooler">than surrounding rural areas</a>. Greenery and vegetation mitigate this by providing shade and filtering air. They also absorb greenhouse gases and other pollutants.</p>
<p>But ecosystem services are under threat everywhere <a href="https://www.iucn.org/news/commission-ecosystem-management/202103/first-ever-global-catalogue-ecosystems-will-enable-coordinated-conservation-efforts#:%7E:text=Gland%2C%20Switzerland%2C%2001%20March%202021,both%20their%20functions%20and%20composition">in the world</a>. Urban development and expansion causes ecological degradation, pollution and an increase in greenhouse <a href="https://www.frontiersin.org/articles/10.3389/fevo.2015.00144/full">gas emissions</a>. This affects ecosystems’ ability to sustainably provide the services that people need for their <a href="https://www.witpress.com/Secure/elibrary/papers/SC20/SC20023FU1.pdf">physical and mental well-being</a>. </p>
<p>In South Africa, these ecosystem services – like wetlands, green spaces and street trees – are grossly under-protected. They are at risk of being damaged irreparably. Intervention is necessary. Regulation in terms of law is one form of intervention.</p>
<h2>South African law</h2>
<p>South Africa has many environmental laws. These draw on a constitutional <a href="https://www.justice.gov.za/legislation/constitution/saconstitution-web-eng.pdf">right</a> to an environment that is not harmful to health and well-being. People have the right to protection of this environment through <a href="https://juta.co.za/catalogue/environmental-law-and-local-government-in-south-africa_28518">legislative and other measures</a>. </p>
<p>The <a href="http://www.saflii.org/za/cases/ZAKZPHC/2013/6.html">High Court</a> has already found that local governments are “in the best position to know, understand, and deal with issues involving the environment at the local level”. But do these governments have the tools they need? To find out, we conducted a <a href="https://research.tilburguniversity.edu/en/publications/municipal-planning-law-and-policy-for-sustainable-cities-in-south">study</a> to see whether South African law is suitable for protecting microclimate regulation in cities. </p>
<p>The main finding was that there are sufficient options in law to achieve this. But many of the legal instruments are underused; they also vary in their effectiveness. Innovative local governance is urgently needed. South African municipalities can and should experiment with a combination of instruments to achieve maximum results in protecting urban ecosystem services. </p>
<h2>Instruments in law</h2>
<p>The combination of national environmental law, local government law and spatial planning law in South Africa has many environmental governance instruments for municipalities to use. These include instruments for strategic and spatial planning and integrated environmental management. Some <a href="https://research.tilburguniversity.edu/en/publications/municipal-planning-law-and-policy-for-sustainable-cities-in-south">examples</a> are municipal plans, land use schemes and environmental management plans. Others include environmental impact assessments and by-laws. </p>
<p>Cities can also use directives, compliance notices, incentives and agreements; one example is environmental management cooperation agreements between municipalities and the private sector. Then there are municipal advisory or ward committees. These instruments are all created in terms of local government and environmental laws promulgated by parliament since 1996. </p>
<p>But it’s the task of every municipality to adopt these instruments and to ensure they are suitable for local conditions. This is what the eThekwini Metro (Durban on South Africa’s east coast) did with its <a href="http://www.durban.gov.za/City_Services/development_planning_management/environmental_planning_climate_protection/Durban_Open_Space/Pages/-What-is-the-Durban-Metropolitan-Open-Space-System.aspx">revised town planning scheme</a>. The scheme looks to protect biodiversity and associated ecosystems.</p>
<p>Our <a href="https://research.tilburguniversity.edu/en/publications/municipal-planning-law-and-policy-for-sustainable-cities-in-south">study</a> showed that environmental governance instruments vary in their ability to protect urban ecosystem services. Many are underexplored. We found that spatial planning and municipal by-laws are two potentially useful instruments.</p>
<p>Take the example of the Ekurhuleni Municipality in the east of Johannesburg. It used <a href="https://www.ekurhuleni.gov.za/council/by-laws-policies/by-laws/ekurhuleni-by-laws-1/45-planting-pruning-removal-and-treatment-of-street-trees-by-law/file.html">by-laws</a> to establish consequences and penalties for damage to or removal of trees. <a href="https://resource.capetown.gov.za/documentcentre/Documents/Bylaws%20and%20policies/Bioregional%20Plan%20for%20City%20of%20Cape%20Town%20-%20(Policy%20number%2044854)%20noted%20on%2019%20August%202015.pdf">Cape Town</a> and <a href="https://www.tshwane.gov.za/sites/business/Bylaws/Draft%20ByLaws/City%20of%20Tshwane%20Bioregional%20Plan%20March%202016%20(EditedAll).pdf">Tshwane</a> municipalities have bioregional plans that provide specifically for climate adaptation measures and ecosystem services.</p>
<h2>Beyond the 2021 local government elections</h2>
<p>The manifestos of the political parties that participated in the 2021 local government elections focused on local economic development and basic services. Environmental conservation and ecosystem protection were mostly overlooked. That’s an oversight: the benefits of these are critical to most other municipal activities. </p>
<p>Ecosystem services protection may not be part of annual municipal audits, but the entire government is obliged to comply with the constitutional environmental right. Everyone has a duty (legal and otherwise) to help address the impact of urbanisation on ecosystem integrity. </p>
<p>The elections ushered in a new start for municipalities. Most cities’ by-laws do not adequately regulate behaviour that may have a negative impact on ecosystem services. Innovative local governance is urgently needed. Municipalities are not bound to use only the legally prescribed instruments or use only a single instrument such as the well-known “municipal integrated development plan”. They are encouraged to try combinations that take local needs, local knowledge and community involvement into account. Municipalities should also compare short-term costs with long-term environmental and societal benefits.</p>
<h2>Conclusion</h2>
<p>Urban ecosystem services sustain life, but aren’t well protected. Newly elected councils should use the available legal tools. The skills, acumen and commitment of municipal administrations are equally important. </p>
<p>It is also up to local communities, scientists and community-based organisations to keep their municipalities to account. They can all contribute to the design and implementation of urban ecosystem protection measures - by complying with the law, for a start.</p><img src="https://counter.theconversation.com/content/171624/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anél du Plessis receives funding from the National Research Foundation of South Africa (Grant number 115581). All errors and viewpoints are the authors' own. The author is affiliated with the North-West University, Faculty of Law and is the Chairholder of the NRF SARChI Chair in Cities, Law and Environmental Sustainability.</span></em></p><p class="fine-print"><em><span>Angela van der Berg has received funding from the National Research Foundation (Grant number 102352) and from the IUCN Academy of Environmental Law (Strategic Grant for Early Career Researchers). All errors and viewpoints are the authors' own. The author is affiliated with the University of the Western Cape (UWC) Faculty of Law, and is the Acting Director of the Global Environmental Law Centre (UWC).</span></em></p><p class="fine-print"><em><span>Maricélle Botes receives funding from the National Research Foundation of South Africa (Grant number 115581), the NWU and the Faculty of Law. All errors and viewpoints are the authors' own. The author is affiliated with the North-West University, Faculty of Law and is a PhD Researcher at the NRF SARChI Chair in Cities, Law and Environmental Sustainability. </span></em></p>Urban ecosystem services sustain life but aren’t well protected.Anél du Plessis, Professor of Law & NRF South African Research Chair in Cities, Law and Environmental Sustainability, North-West UniversityAngela van der Berg, Acting Director of the Global Environmental Law Centre, University of the Western CapeMaricélle Botes, PhD Researcher at the South African Research Chair in Cities, Law and Environmental Sustainability (CLES), North-West UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1682562021-12-08T04:01:55Z2021-12-08T04:01:55ZNature is hiding in every nook of Australia’s cities – just look a little closer and you’ll find it<figure><img src="https://images.theconversation.com/files/436264/original/file-20211208-21-1kmvpvd.jpg?ixlib=rb-1.1.0&rect=37%2C322%2C8238%2C5186&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Thanks to technological advances, citizen science has experienced unprecedented global growth over the past decade. It’s enabled millions of people to get involved in science, whether by gathering data, sharing health information or helping to map galaxies.</p>
<p>And just because you live in a city, it doesn’t mean you can’t observe, learn about and contribute to scientific understanding of the natural world. Sometimes, it just means looking a little closer. </p>
<p>However, <a href="https://link.springer.com/article/10.1007%2Fs11252-021-01187-3">our recent study</a> revealed in Australia, the number and diversity of urban ecology citizen science projects is relatively low.</p>
<p>This is despite cities being important places of conservation and discovery. There’s enormous value in citizen science projects that encourage urbanites to learn about what is often, quite literally, on their doorsteps.</p>
<figure class="align-center ">
<img alt="Two woman tag butterfly" src="https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436266/original/file-20211208-25-4348qs.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">Urban citizen scientists are a valuable, untapped resource in Australia.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Cities are important for conservation</h2>
<p>Recent COVID-19 restrictions mean many of us became more intimately connected to the environment around us. But there is still an overriding <a href="https://conbio.onlinelibrary.wiley.com/doi/10.1111/cobi.13193">perception</a> of urban areas as wastelands devoid of rich and diverse species.</p>
<p>It’s true that for many centuries, vegetation in urban areas has been removed to make way for buildings, roads and other human structures. In many cases, this had led to a more homogeneous composition of species and, in Australia’s case, a seeming predominance of introduced plant and animal species.</p>
<p>However, recent <a href="https://doi.org/10.1002/fee.2032">literature</a> has shown cities remain vital habitats for many native species. This includes threatened species such as the <a href="https://onlinelibrary.wiley.com/doi/10.1111/geb.12404">fringed spider orchid</a>, found only in Greater Melbourne.</p>
<p>Recent research <a href="https://esajournals.onlinelibrary.wiley.com/doi/10.1002/fee.2032">found</a> 39 nationally threatened species live only in Australian cities and towns, including the western swamp tortoise in Perth and the angle-stemmed myrtle in Brisbane. </p>
<p>It’s important to preserve native vegetation remnants in towns and cities, as well as traditional urban green spaces like parks, cemeteries and backyards. </p>
<p>But it’s just as important to understand which species call these areas home and why. That’s where citizen science can play a big role.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/where-the-wild-things-are-how-nature-might-respond-as-coronavirus-keeps-humans-indoors-134543">Where the wild things are: how nature might respond as coronavirus keeps humans indoors</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="white flower and leaves" src="https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=301&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=301&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=301&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=378&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=378&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436280/original/file-20211208-188518-bgx9vh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=378&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The angle-stemmed myrtle is found only in Brisbane.</span>
<span class="attribution"><span class="source">Logan City Council</span></span>
</figcaption>
</figure>
<h2>What we found</h2>
<p>We set out to examine the extent to which urban ecology projects in Australia harnessed the resources of citizen scientists. We did this by analysing the projects <a href="https://biocollect.ala.org.au/acsa#isCitizenScience%3Dtrue%26isWorldWide%3Dfalse%26max%3D20%26sort%3DnameSort">listed</a> in the Citizen Science Project Finder, hosted by the Atlas of Living Australia. </p>
<p>Of 458 active citizen science projects, only 19 (or 5.3%) were focused on urban environments. Given the number of urban residents in Australia, this constitutes a significant under-representation of projects tailored for these people.</p>
<p>Most of the 19 projects focused on four major cities – Sydney, Brisbane, Perth and Adelaide – while other major cities were notably omitted.</p>
<p>Eight projects focused on broad census approaches – essentially ad hoc observations focused on birds or all flora and fauna in a region.
Documenting the presence of various species in urban areas is important. But there’s potential for citizen scientists to help answer more targeted research questions.</p>
<p>For example, grey-headed flying foxes have been <a href="https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2005.00005.x">documented</a> re-colonising habitat in Melbourne they were once absent from. As cities continue to grow, knowing which species can persist and which have been pushed out is incredibly valuable – and citizen scientists can help in this task.</p>
<p>Also, many of the 19 projects did not provide an easy way to participate, such as easy links to platforms to record and upload data. We were also unable to find scientific papers where results from any of the 19 projects had been published.</p>
<p>Publications would further strengthen the validity of a citizen science approach in urban environments and add another way to measure success.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/our-turtle-program-shows-citizen-science-isnt-just-great-for-data-it-makes-science-feel-personal-155142">Our turtle program shows citizen science isn't just great for data, it makes science feel personal</a>
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</em>
</p>
<hr>
<figure class="align-center ">
<img alt="flying foxes hand upside down on branch" src="https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436277/original/file-20211208-141979-1rfi2bs.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">Grey-headed flying foxes have recolonised parts of Melbourne.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Citizens are good for science</h2>
<p>More than 70% of Australians live in a major city. This offers a large pool of potential participants in citizen science projects. </p>
<p>And cities are home to people from a variety of cultures, backgrounds, ages and mobilities. There is increasing <a href="https://academic.oup.com/jid/article/220/Supplement_2/S33/5552350">acknowledgement</a> that science is enhanced by increasing the diversity of people involved. So a greater number of urban citizen science projects would be good for science.</p>
<p>What’s more, urban projects can provide data from places not typically accessible to professional scientists such as backyards and school grounds. They also allow for the collection of observation-rich and continuous data, which is rare even in professional settings.</p>
<p>And of course, citizen science projects benefit the participants themselves – encouraging people to get outdoors, get active and connect more deeply with nature.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-counting-birds-to-speaking-out-how-citizen-science-leads-us-to-ask-crucial-questions-166673">From counting birds to speaking out: how citizen science leads us to ask crucial questions</a>
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</em>
</p>
<hr>
<figure class="align-center ">
<img alt="woman shows frog to school students" src="https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436278/original/file-20211208-19-1ll5ixn.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">Citizen science can provide data from places professional researchers can’t always access, such as schools.</span>
<span class="attribution"><span class="source">Australian Museum</span></span>
</figcaption>
</figure>
<h2>A tool for measuring change</h2>
<p>Increasing citizen science in cities could help to shift an overriding narrative that cities are not important places for biodiversity. This may in turn afford greater concentrated effort towards conserving remaining urban green spaces. </p>
<p>Citizen science could help answer key ecological questions about urban environments. For example, <a href="https://theconversation.com/birdwatching-increased-tenfold-last-lockdown-dont-stop-its-a-huge-help-for-bushfire-recovery-141970">research</a> last year showed how citizen scientists helped document species seeking refuge in urban areas following Australia’s horrific 2019-20 bushfires. Expanding such an approach could lead to a better understanding of how cities function as biodiversity refuges. </p>
<p>And a greater focus on citizen science in cities would also enable residents to engage in their surroundings, share their knowledge and help inform the management of the environment around them.</p><img src="https://counter.theconversation.com/content/168256/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Erin Roger is a Projects Manager for the Atlas of Living Australia based in CSIRO Sydney. Erin is also the former Chair of the Australian Citizen Science Association </span></em></p><p class="fine-print"><em><span>Alice Motion is an Associate Professor at the School of Chemistry at the University of Sydney. She receives funding from a Westpac Research Fellowship and a NSW Education Grant. She is Deputy Director (Outreach and Training) for the Sydney Nano Institute, Co-Chair of the Charles Perkins Centre Citizen Science Node and a member of the Australian Citizen Science Association Management Committee in her role as host representative.</span></em></p>There’s enormous value in citizen science projects that encourage urban-dwellers to learn about what is often, quite literally, on their doorsteps.Erin Roger, Citizen Science Program Lead, CSIROAlice Motion, Associate professor, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1517992021-07-01T16:56:18Z2021-07-01T16:56:18ZTen talismans for a new understanding of cities in post-pandemic times<figure><img src="https://images.theconversation.com/files/409177/original/file-20210630-21240-9ibvts.jpg?ixlib=rb-1.1.0&rect=0%2C4%2C1386%2C1033&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Urban green spaces are essential for the well-being of both human and and non-human residents of a city. </span> <span class="attribution"><span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>For more than a year and a half, the SARS-CoV-2 pandemic has kept the world locked down. Schools, universities, cafés and restaurants, cultural institutions and stores have been closed for long stretches of 2020 and 2021. In many parts of the world, travel has slowed to a crawl and sometimes stopped completely. While the number of flights is climbing as some restrictions are lifted, they remain <a href="https://www.icao.int/sustainability/Pages/Economic-Impacts-of-COVID-19.aspx">significantly lower</a>. Even 18 months later, it feels as if life itself has come to a relative standstill. </p>
<p>Mandatory <a href="https://theconversation.com/cities-are-at-centre-of-coronavirus-pandemic-understanding-this-can-help-build-a-sustainable-equal-future-136440">social distancing and movement restrictions</a> have profoundly changed what we could do, particularly for those living in cities across the globe. At the same time, <a href="https://www.thenatureofcities.com/2020/05/04/enabling-access-to-greenspace-during-the-covid-19-pandemic-perspectives-from-five-cities/">green spaces within urban areas</a> allowed city dwellers to get some air and compensate for the absence of holiday and travel options. As car travel fell, flora and fauna were even able to (temporarily) make a <a href="https://www.bbc.com/news/world-52459487">surprise return to urban centres</a>.</p>
<h2>Reflections from urban scholars</h2>
<p>During the last year, urban scholars – be they planners, ecologists, social geographers, or risk researchers – have had the opportunity reflect upon the following issues: </p>
<ul>
<li><p>The process, form, density and extent of <a href="https://www.nature.com/articles/s41893-019-0436-6">urbanisation</a> and the related loss or regeneration of ecosystems inside and around cities.</p></li>
<li><p>The extent and accessibility of green spaces in cities for recreation, public health and refuge.</p></li>
<li><p>How nature and humans are <a href="https://www.nature.com/articles/s42949-020-00008-4">co-habiting</a> and what we can do to prevent <a href="https://link.springer.com/article/10.1007/s13280-016-0809-2">future zoonoses</a>.</p></li>
<li><p>The role that science-based facts, expert knowledge and social media have in shaping the public discourse about cities, and their material and immaterial matter.</p></li>
</ul>
<p>Here are 10 premises – I call them “talismans” to emphasise that they’re opportunities – that can act as a guide to reflecting about the above issues.</p>
<h2>1. Co-habitational distancing, not social distancing</h2>
<p>Humans and nature should go for a new kind of <a href="https://link.springer.com/article/10.1007/s13280-020-01449-y">co-habitational distancing</a> based on mutual respect. During the pandemic, we have learned what social distancing is – to keep distance to safeguard the others. This was a good and a successful strategy, but we applied this strategy exclusively to the human society. Following the idea of <a href="https://theconversation.com/the-one-health-concept-must-prevail-to-allow-us-to-prevent-pandemics-148378">One Health</a>, we should extend the idea of distancing to all living creatures on our planet. This would help preserve ecosystems and safeguard their health, and in so doing, safeguard ours. </p>
<p>Mutual respect means distancing as humans and animals spheres overlap and let them interact, but not in most cases and not everywhere. Co-habitational distancing means sharing land for common needs as well as spare land for individual interests and needs.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/388592/original/file-20210309-15-7ducus.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">Green spaces give human, animals and plants a place to breath.</span>
<span class="attribution"><span class="license">Fourni par l'auteur</span></span>
</figcaption>
</figure>
<h2>2. Encourage co-habitation of nature and humans in cities</h2>
<p>Diverse cities must be exactly that. They require a respectful attitude for all human beings as well as nonhuman beings. In a <a href="https://www.cogitatiopress.com/urbanplanning/article/view/1901">superdiverse city</a>, space is required. This is what we learned for humans – Setha Low’s <a href="https://www.researchgate.net/publication/285787631_Public_space_and_diversity_Distributive_procedural_and_interactional_justice_for_parks">“Public space and diversity”</a> is a key text – and the same is true for the other creatures with whom we share this planet. </p>
<p>In cities we already have excellent forms that enable us to realise different intensities of <a href="https://link.springer.com/article/10.1007/s13280-020-01449-y">human-nature co-habitation</a> – gardens, urban parks, zoological gardens, brownfields and nature reserves are all spaces that allow for either cohabitation or distancing.</p>
<h2>3. Guaranteeing rights not only for city dwellers, but also for nature</h2>
<p>The pandemic clearly revealed the double standards we have about humans (societies) and nature (ecosystems). We must drop this double standard and work to <a href="https://en.wikipedia.org/wiki/Reconciliation_ecology#:%7E:text=Reconciliation%20ecology%20is%20the%20branch,biodiversity%20in%20human%2Ddominated%20ecosystems">ensure rights for both humans and nature</a>. We must also invest the time and effort required to explore what are rights of nature not only in the establishment of reserves and national parks but also in daily co-habitation.</p>
<h2>4. Cities can show how we can reduce land, material and food consumption</h2>
<p>Getting healthier and happier while demanding less from nature is essential for us keep more core habitats intact. For decades, urban ecologists have dealt with core habitats and buffer zones. We have the theoretical knowledge, but we betray this knowledge with misguided ideas of endless growth and higher and higher per-capita living. </p>
<p>But there is hope: In cities such as New York, <a href="https://theconversation.com/cities-are-at-centre-of-coronavirus-pandemic-understanding-this-can-help-build-a-sustainable-equal-future-136440">land prices have soared</a> and per-capita living space has dramatically declined. In such dense urban areas, can we find approaches that will enable us to preserve space for nature? All organisms need space, after all – humans for housing and animals for hunting and nesting. Significant undisturbed ecosystems would be the best strategy for preserving the quality of life as well as reducing the chance of future pandemics.</p>
<h2>5. Learning from what the arrival of Covid-19 is telling us</h2>
<p>Rethinking the ability to access basic resources, wealth and education is essential. Urban societies can enable all their residents have better health and escape poverty. This in turn will reduce susceptibility to the pandemics and root out the inequalities in our societies that lead to overproduction, food waste, malnutrition and obesity and extreme urbanisation, all at once. Here too, Setha Low’s <a href="https://www.researchgate.net/publication/285787631_Public_space_and_diversity_Distributive_procedural_and_interactional_justice_for_parks">three-dimensional concept</a> is essential.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409180/original/file-20210630-21240-48gj05.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=560&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Manchester street scene.</span>
</figcaption>
</figure>
<h2>6. Reasoning from what happened and concluding from factual evidence</h2>
<p>In pandemic and post-pandemic times, it is worth asking questions as a way to provokes deeper learning. In similar times, what did our ancestors do? What can we see in the shape and morphology of cities that were witnesses to past pandemics? What can urban history and city regulations and planning literature tell us about earlier solutions to pandemic situations? What worked and what did not? Are there tipping points? Are there points of return?</p>
<h2>7. Make evidence the base of policy advice and decisions</h2>
<p><a href="https://www.sciencedirect.com/science/article/abs/pii/S1618866718303352?via%3Dihub">Green cities</a> could be a sustainable, space-saving way for humans to settle at this planet, including green roofs, rooftop gardens and “living walls”. But unless developed in a smart and comprehensive way, they won’t be enough to compensate for global ecosystems loss – the decline of Brazilian tropical rain forests’ for soybean fields or the clear-cutting in South East Asia for palm-oil plantations, for example. The levels of both impacts – global and local – do not fit, and nor do the benefits and burdens hit the global urban and rural populations in a similar/equal way (<em>Haase</em>, 2020).</p>
<h2>8. Social media data can build awareness our urban social-ecological systems</h2>
<p>Data gathered by citizen scientists and shared through social media can provide a wealth of information (<a href="https://static1.squarespace.com/static/552ec5f5e4b07754ed72c4d2/t/5be1dae270a6adf7bb5a6609/1541528292607/ilieva+and+mcphearson_+nature+sustainabilty+2018.pdf"><em>Ilieva and McPhearson</em>, 2014</a>. What new plants and insects have arrived? Where do animals show irregular behaviour? What species have disappeared? The direct, almost real-time input that local administrations can obtain has the potential to establish more meaningful connections between citizens and institutions, as well as between citizens and the nature around them. This will bringing new synergies to the management of urban ecosystems and the vital services it provides to humans and other living organisms in the city. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=314&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=314&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=314&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=394&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=394&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409181/original/file-20210630-21256-hrj1mq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=394&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chequamegon, Nicolet National Forest.</span>
<span class="attribution"><a class="source" href="https://www.wpr.org/tribal-forests-more-diverse-sustainable-surrounding-forests">Joshua Mayer/WPR</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>9. Use traits to expand our understanding of environmental changes</h2>
<p>Through their direct relation to ecosystem services such as cooling and fresh air, easy-to-understand <a href="https://www.nature.com/articles/s42949-020-00008-4">traits</a> can be an entry point for awareness of nature. To do so, it is vital for us to understand the diverse characteristics of urban society, including cultural background, physical mobility, gender, age, education levels, access to information, purchasing power and political influence. All these factors affect the needs, preferences, and values of individuals and groups, and the way each interpret human-nature relationships. </p>
<p>Large-scale monitoring needs to be coupled with <a href="https://www.sciencedirect.com/science/article/pii/S0169204620308860">in-depth understanding of response mechanisms and their impact on ecosystem functions</a>. Only by taking all these factors into account can we create more inclusive urban systems that foster multiple benefits for both people and biodiversity.</p>
<h2>10. Understand cities as complex systems at all scales</h2>
<p>Cities are complex systems from their smallest unit up to the largest. This includes:</p>
<ul>
<li><p>Individuals: personal perceptions, behaviour and activism.</p></li>
<li><p>Local areas: neighbourhood greening initiatives, urban gardening, <a href="https://link.springer.com/article/10.1007%2Fs13280-014-0506-y">nature stewardship</a></p></li>
<li><p>Districts : environmental justice, access to public green spaces</p></li>
<li><p>Cities: periurbanization and cities’ involvement in <a href="https://www.ufz.de/index.php?en=20939&pub_id=22205">urban telecouplings</a> and <a href="https://www.pnas.org/content/109/20/7687">teleconnections</a>, politicians and parties that promote nature-destroying policies, investors funding the heedless exploitation of nature. </p></li>
</ul>
<p>Taken together, these 10 “talismans” can guide us when reflecting about the challenging times in which we’re all living. In particular, they can help us understand how the form, density and extent of urbanisation interact with ecosystems at every level, driving positive or negative change. We think too rarely about feedback loops, too often we ignore the cognitive gap, too often we follow linear thinking schemes despite the fact that we know better – and must do better. </p>
<hr>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=121&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=121&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=121&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=152&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=152&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202296/original/file-20180117-53314-hzk3rx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=152&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em>Created in 2007, the Axa Research Fund supports more than 500 projets around the world conducted by researchers from 51 countries. Find out more about Dagmar Haase’s work on the <a href="https://www.axa-research.org/en/projects/haase-dagmar">dedicated site</a></em>.</p><img src="https://counter.theconversation.com/content/151799/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dagmar Haase has received funds for her research from the Axa Research Fund.</span></em></p>As we look beyond a world besieged by Covid-19, the relationship between humans and nature in our cities must be shaped and reclaimed.Dagmar Haase, Professor of Landscape Ecology, Humboldt Universität zu Berlin, Helmholtz Centre for Environmental Research-UFZLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1628102021-06-28T19:23:36Z2021-06-28T19:23:36ZHow urban gardens can boost biodiversity and make cities more sustainable<figure><img src="https://images.theconversation.com/files/408460/original/file-20210625-27-1fvl7ha.jpg?ixlib=rb-1.1.0&rect=107%2C71%2C5748%2C3206&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Part of the answer to a more functional and sustainable city may lie in your garden.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 250px; border: none; position: relative; z-index: 1;" src="https://narrations.ad-auris.com/widget/the-conversation-canada/how-urban-gardens-can-boost-biodiversity-and-make-cities-more-sustainable" width="100%" height="400"></iframe>
<p>In building cities, we have created some of the harshest habitats on Earth — and then chosen to live in them. </p>
<p>Temperatures in cities are typically 2 C to 3 C warmer than those of the surrounding landscape. Pollution levels and noise can reach levels seen few other places on Earth. <a href="https://doi.org/10.2134/jeq2015.11.0567">Too much drainage leaves soils dry in the heat, but the sealed surfaces of roads and sidewalks lead to flooding when it rains</a>. </p>
<p>Because <a href="https://www.statista.com/statistics/271208/urbanization-in-canada">cities now house over 80 per cent of Canadians</a>, their impact on the environment extends far beyond the city limits. Cities are now driving large-scale environmental changes such as elevated pollution levels, climate change and habitat loss. </p>
<p>We need to find solutions to creating more sustainable and functional cities. Part of the answer may lie in your garden.</p>
<h2>Plants allow the city to sweat</h2>
<p>The field of urban ecology is relatively new, but over the past three decades it has shed light on how green infrastructure — trees and other plants of greenspaces, gardens and wetlands — can offer solutions to the issues faced by urban development. </p>
<p>The few ecological studies done within cities prior to 1990 were based on isolated greenspaces. In the 1990s, there was a shift from studying ecology <em>in</em> cities towards studying the ecology <em>of</em> cities, where <a href="https://doi.org/10.1002/ehs2.1229">the entire city was seen as a coherent, functioning ecosystem</a>, which led to the interdisciplinary field of urban ecology. </p>
<p>Urban ecology helps us understand how and why green infrastructure provides ecosystem services — the specific benefits provided by components of the ecosystem — that improve the livability and sustainability of urban areas. </p>
<p>For example, vegetation lowers the temperature of the city by 1 C to 9 C. This is not only a matter of providing shade — transpiration from the leaf surface area allows the city to sweat. Leaves also slow down raindrops, and roots allow rain to infiltrate the ground, reducing surface runoff. Further, the foliage <a href="https://doi.org/10.1007/s10980-013-9912-y">traps particulate pollution and reduces noise</a>.</p>
<h2>The importance of plant-based solutions</h2>
<p>The importance of this can be seen in cities across the United States, where the link between demographics and urban planning has been well-studied. Decades of limited greenspace development in <a href="https://www.nytimes.com/2020/08/26/climate/racist-urban-planning.html">neighbourhoods dominated by people of colour have left these areas both warmer and less liveable than those of adjacent, whiter neighbourhoods</a>. Differences in vegetation cover have become a driver for socio-economic and racial discrepancies in well-being. </p>
<p>The addition and maintenance of green infrastructure is now central to urban planning in most cities. This includes planting trees and bushes, naturalizing parks, restoring wetlands and promoting other forms of green infrastructure such as <a href="https://www.toronto.ca/city-government/planning-development/official-plan-guidelines/green-roofs/">green roofs</a>. Some cities, including Edmonton, have launched <a href="https://www.edmonton.ca/activities_parks_recreation/parks_rivervalley/goat-pilot-project.aspx">goat programs to control noxious weeds</a>. </p>
<figure class="align-center ">
<img alt="Front yard of a house" src="https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408461/original/file-20210625-18-wnvq68.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">Privately owned gardens can make up a large portion of a city’s greenspace and can have very high functional diversity.</span>
<span class="attribution"><span class="source">(Karen Christensen-Dalsgaard)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>A complicating factor is that much of the urban greenspace is found in privately owned gardens. Depending on the city, gardens can make up between 16 and 40 per cent of the total urban land cover, and between <a href="https://doi.org/10.1016/j.tree.2009.07.016">35 and 86 per cent of the total greenspace</a>. Governments have little influence over these areas, leaving it up to individual people to make the right decisions.</p>
<h2>How to garden for your community</h2>
<p>The best decisions on how to garden for ecosystem services and healthy habitat depends on what you are trying to achieve, but some approaches transcend most objectives.</p>
<p>Sealed surfaces such as concrete or asphalt are the bane of urban development. They increase heat retention and surface runoff, and are inhospitable to almost all organisms, contributing to the low biodiversity seen in some urban areas. </p>
<p>Breaking up sealed surfaces and planting vegetation improves biodiversity, flood mitigation and cooling. The extent to which vegetation modifies the micro-climate varies with plant composition and structural features.</p>
<p>A recent study compared different types of <a href="https://doi.org/10.1016/j.ufug.2021.127007">low-height green infrastructure such as lawns, meadows and low shrubland in Montréal</a>. Surface temperatures, measured using infrared thermal imaging, were higher in plots with less plant volume. Lawns, for example, were warmer than flower meadows or shrubland. </p>
<figure class="align-center ">
<img alt="A bright green lawn" src="https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=383&fit=crop&dpr=1 600w, https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=383&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=383&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/408462/original/file-20210625-21-sy80d0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Flower meadows have more beetles, spiders, centipedes, butterflies, bees and other insects than lawns.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Arthropods — such as beetles, spiders and centipedes as well as butterflies, bees and other insects important for pollination — were more abundant and diverse in areas with more plant varieties. Flower meadows had an approximately 50 per cent higher arthropod richness than lawns. </p>
<p>Your neighbour’s lawn might be greener, but your overgrown shrubbery likely provides better habitat for arthropods and other animals, and ecosystem services such as heat reduction and water infiltration.</p>
<h2>Urban greenspaces can be a refuge</h2>
<p>The value of gardens as biodiversity refuges relates to a concept called functional diversity. This is a measure of how many different functional groups that are present in a habitat. A functional group is a set of organisms that share key characteristics such as food choice, reproductive strategies and behaviours. </p>
<p>With vegetation, a high functional diversity implies that there is a variety of different types plants present — grasses, other herbaceous annuals and perennials, bushes, broad-leaved trees and coniferous trees. </p>
<p>Gardens with high functional diversity excel in most ecosystem services. The multilayered canopy and root systems are more effective in promoting water infiltration into the soil. Deeper roots allow transpiration during hotter days. And a greater functional diversity of plants tends to result in a greater variety of animals living in the garden.</p>
<p>Because of this, properly managed gardens can replace the habitat lost due to urban development, making <a href="https://doi.org/10.1038/s42949-020-00010-w">urban greenspaces increasingly important as refuges for native biodiversity</a>. Planting functionally different and, ideally, native species that extend the period of flowering and fruiting throughout the growing season provides excellent habitat for <a href="https://doi.org/10.1002/ece3.1941">pollinating insects</a>, <a href="https://doi.org/10.1016/j.landurbplan.2016.04.011">birds</a> and other animals. The <a href="https://doi.org/10.1111/1365-2664.13475">biodiversity of gardens managed for habitat improvement can match that of natural areas</a>. </p>
<p>If you own a garden, you own one part of the solution to creating liveable and sustainable cities. <a href="https://cwf-fcf.org/en/explore/gardening-for-wildlife/tools/">It is up to you to choose what to do with it</a>. The choices you make will affect the urban ecosystem you are part of, determine how your city functions and how it interacts with the surrounding semi-urban, rural and wild areas.</p><img src="https://counter.theconversation.com/content/162810/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Karen Kirstine Christensen-Dalsgaard collaborates with the City of Edmonton on research projects related to urban Ecology and urban plant physiology</span></em></p>Cities are among the harshest habitats on Earth. But when planned properly, private gardens can help improve their liveability.Karen K. Christensen-Dalsgaard, Assistant Professor in Plant Biology and Urban Ecology, MacEwan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1557682021-02-25T13:52:06Z2021-02-25T13:52:06ZRed kites and ravens swooped through Elizabethan London – and helped keep the city clean<p>We sometimes think of cities as concrete deserts inhabited only by humans, pigeons and rats. But that has never been true. In London, for example, the streets are lined with <a href="https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/london-plane/">plane trees</a>, foxes come out at night, and starlings and house sparrows whistle from the rooftops.</p>
<p>If you’ve driven on the M4 motorway out of the UK capital you might have spotted something bigger picking at roadkill. Common ravens and <a href="https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/red-kite/">red kites</a> are larger than hawks and falcons, and though they may peck at the city’s outskirts today, in the time of Shakespeare and the Great Plague they were common inside London too. </p>
<p>These carrion birds would nest in the city’s trees and high buildings and swoop through the streets eating waste food and offal. Some stories even maintain that they were strictly protected by law and killing them was punishable by death.</p>
<p>How did the average Londoner feel about sharing their city with these wild and imposing creatures? For my new report, <a href="https://t.co/zuetZF3pqx?amp=1">published in The London Journal</a>, I combed the historical record for travellers’ accounts, natural history notes and laws and discovered a lost world of mischief, humour and inter-species harmony.</p>
<figure class="align-center ">
<img alt="A raven picks at a rabbit carcass on tarmac." src="https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/386423/original/file-20210225-15-sff7ge.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">Ravens are often found scavenging carcasses.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/raven-eating-remains-feral-rabbit-beside-1751236649">D.Cunningham/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Tall tales from travellers</h2>
<p>The best evidence for ravens and red kites in London comes from the early modern period, between 1466 and 1777. In this time, travellers to London described these birds in daily life in some of the richest accounts left to historians. Their stories often use the ravens and red kites to paint London as a particularly wild and uncivilised place. </p>
<p>Sadly, these early travelogues aren’t the most reliable sources. Just as modern tourists tend to exaggerate how unique and exotic the places they visit are, the same was true in the past. Historical and <a href="https://revistas.uam.es/archaeofauna/article/view/8855/9076">archaeological evidence</a> suggests that ravens and kites were not unique to London. They have lived in many urban areas across Britain and elsewhere in Europe, at least since the Roman period.</p>
<p>That’s not to say the large birds were model Londoners. One of Britain’s most respected naturalists of the time, William Turner, wrote in a letter published in 1555 that:</p>
<blockquote>
<p>Such is the daring of our kites, that they often dare to take bread from children, fish from women, and cloths from hedges and from the hands of men. Indeed, very often they will take the hats from people’s heads during the time when they are nesting.</p>
</blockquote>
<p>Incidentally, this habit of stealing cloth has endured among red kites. Today they even seem to have a special fondness <a href="https://ww2.rspb.org.uk/our-work/rspb-news/news/details.aspx?id=tcm:9-220496">for stealing underwear</a>.</p>
<p>So, if people at the time thought of ravens and red kites like we think of gulls that dive bomb people enjoying fish and chips, why did early modern Londoners put up with them?</p>
<figure class="align-center ">
<img alt="An engraving depicting a Medieval city skyline filled with large birds." src="https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&rect=0%2C0%2C1337%2C2044&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=916&fit=crop&dpr=1 600w, https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=916&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=916&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1151&fit=crop&dpr=1 754w, https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1151&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/385910/original/file-20210223-19-1sf1rpa.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1151&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Hortus Sanitatis (the first natural history encyclopaedia) depicts London life at the end of the 15th century.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Hortus_Sanitatis#/media/File:Hortus_De_avibus.jpg">Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Birds of a feather</h2>
<p>Wenzel Schaseck, a traveller from what is now the Czech Republic, reported in 1466 that it was a capital offence to harm red kites in London. Pierre Belon, a naturalist from France reported in 1555 that anyone caught doing violence to ravens anywhere in England would receive a heavy fine. The trouble is, I’ve looked and I can’t find any statute which protects ravens and kites. In fact, the Act Against Destruction Of Wildfowl (1533-4) actually encourages people to destroy ravens and other inedible species, like red kites. </p>
<p>The closest thing to a protection law which exists is in the Grain Act (1566), which set bounties on the heads of most of our wildlife for pest control. This act included an exception: bounties would not be paid for ravens and red kites found in towns and cities, which meant that no one would benefit from hunting the urban scavengers.</p>
<p>But why were their populations in London preserved for so long? John Taylor, known as the Water Poet – a celebrity Londoner of the 17th century – gives a more convincing reason for why people put up with the birds:</p>
<blockquote>
<p>Ravens, kites, crows, and many other birds of prey, are tolerated to live unhurt, not for any good that is in themselves, but because they do good offices in devouring and carrying away our garbage.</p>
</blockquote>
<p>Londoners living in a time of unreliable waste disposal and plague epidemics seemed to value the industrious carrion-eating birds for the relative cleanliness they afforded. Today, we might even say they performed a useful ecosystem service by contributing to the city’s sanitation. Ravens and red kites in turn seem to have loved the messy, bustling London streets. They fitted in perfectly. Perhaps they didn’t need legal protection.</p>
<p>Ravens and red kites were lost from London in the 18th century and were soon eradicated across most of the rest of Britain. Improvements in sanitation, bounty hunting outside of the city, and the felling of trees may all have played a part in their departure from the capital’s skies.</p>
<p>But today, 300 years later, things are looking better. Ravens and red kites have recovered much of their lost range and the birds have even started to return to London, with both birds now occasionally nesting <a href="https://lnhs.org.uk/images/publications/LBR2016/LBR-2016-corrected.pdf">within the city limits</a>. Can Londoners, ravens and red kites learn to live together again?</p><img src="https://counter.theconversation.com/content/155768/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lee Raye 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>Plague-wary Londoners tolerated mischievous red kites and ravens for their services to the city’s sanitation.Lee Raye, Associate Lecturer in Arts and Humanities, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1545402021-02-15T13:12:52Z2021-02-15T13:12:52ZSave the trees: Never-ending construction in cities threatens the urban forest<figure><img src="https://images.theconversation.com/files/383404/original/file-20210209-17-alv26t.jpg?ixlib=rb-1.1.0&rect=21%2C0%2C7296%2C2984&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Several large cities have set ambitious targets for increasing their tree canopy. The city of Montréal has adopted an action plan that aims to plant 185,000 trees by 2025. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>City trees are important: they purify the air, reduce <a href="https://www.canada.ca/en/services/health/publications/healthy-living/reducing-urban-heat-islands-protect-health-canada.html">heat islands</a>, help regulate the water cycle and provide immense health benefits. Yet unbridled development <a href="https://doi.org/10.2134/jeq2015.11.0567">threatens the survival of the urban forest</a> and the full range of <a href="https://www.iucn.org/commissions/commission-ecosystem-management/our-work/cems-thematic-groups/services">ecosystem services</a> it provides. </p>
<p>The magnitude of these services is closely linked to the importance of the canopy, which is the area covered by treetops. It is generally characterized by an index that relates the sector covered by the tops to the total size of an area.</p>
<p>A recent study of the natural canopy in the areas covering Québec City, Beaupré, l'Île d'Orléans, Lévis and other communities along the St. Lawrence River found it <a href="https://cmquebec.qc.ca/wp-content/uploads/2019/09/2019-09_Valeur-%C3%A9conomique-ecosyst%C3%A8mes_UQO_Rapport-final.pdf">generates more than $1.1 billion in annual benefits</a>.</p>
<p>Water supply, flood reduction, air quality improvement and carbon sequestration were among the ecosystem services — the benefits people derive from the ecosystem — that were considered. In this context, several major cities have set ambitious canopy expansion targets.</p>
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À lire aussi :
<a href="https://theconversation.com/sustainable-cities-after-covid-19-are-barcelona-style-green-zones-the-answer-150774">Sustainable cities after COVID-19: are Barcelona-style green zones the answer?</a>
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<p>However, these objectives face several significant challenges. Residential construction and the development and renovation of infrastructure tend to reduce the urban canopy. Part of this reduction is directly related to the space occupied by the infrastructure, while another part is the result of damage to trees during installation.</p>
<p>As a forest engineer and professor of <a href="http://www.silviculturecanada.ca/index.html">silviculture</a> and urban forestry, my research investigates the stability of trees against wind in natural, urban and rural environments. I was interested in the effect of species, soil type and apparent defects on the resistance to stem breakage and uprooting.</p>
<h2>Direct damage</h2>
<p>Construction in a wooded environment brings about general changes in the trees’ growing environment. By opening the canopy, trees become exposed to stronger winds, which increases their need for water and can compromise their stability. </p>
<p>During construction in a wooded environment, surfaces may become impermeable. This reduces water flow into the soil and promotes water runoff. In combination, these two factors can lead to water stress and eventually trees dying a few years after construction.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An excavator on an urban tree-lined street" src="https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/383408/original/file-20210209-13-w4m35g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Construction work near trees often involves excavation that damages part of the root system. Work is carried out here on St-Denis Street in Montréal.</span>
<span class="attribution"><span class="source">(Author provided)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Construction near existing trees can cause direct damage to the aerial part of the tree, which is quite easily visible. Damage to the root system will be much more subtle but can have more important consequences. </p>
<p>Roots play many roles including the accumulation of reserves, anchoring to the ground and the removal of water and nutrients. Damage to the roots will affect their ability to perform these various functions, with consequences on the general functioning of the tree.</p>
<p>Construction work near trees often involves excavation that damages part of the root system. Studies have found that <a href="https://doi.org/10.1016/j.ufug.2020.126734">cutting the roots can reduce resistance to uprooting</a> — this effect may persist for several years after the initial damage.</p>
<p>The magnitude of the effect is related to the amount of root loss, which is a function of <a href="https://doi.org/10.1016/j.ufug.2018.10.015">distance from the trunk</a>. Although root extension may extend beyond the space below the crown, it is generally considered that the most important part is in this area. The effect of root cutting on tree stability will also depend on <a href="http://publications.cirad.fr/une_notice.php?dk=549799">the configuration of the root system</a>.</p>
<h2>Growth reduction</h2>
<p>The difficulty for the tree to replenish its water reserves following root damage can lead to the <a href="https://www.westminster.gov.uk/sites/default/files/cd_8.40_part_8_-_response_of_roadside_trees_to_root_severance_benson_et_al.pdf">closure of stomata</a>, the pores that control gas exchange during photosynthesis. This closure can then lead to a reduction in growth. Following root destruction, the tree redirects the products of photosynthesis to rebuild the root system at the expense of the growth of the aerial part of the tree.</p>
<p>In some cases, the effects on growth and mortality will be limited, but severely damaged trees will take time to recover, which may make them more vulnerable to other stresses. When root loss is too great, the tree will decline over several years and eventually die. When the root system is able to rebuild itself, growth can resume its normal rhythm. Recovery is more likely when the trench is temporary and a material conducive to root development is put back in place at the end of the work.</p>
<h2>Further studies needed</h2>
<p>Soil compaction by machinery or the addition of soil above the original level can change the aeration of the soil and its water conditions. The diffusion of air to the roots and the diffusion of CO2 produced by root respiration will then be reduced, thus hindering their proper functioning. </p>
<p>However, the effect of soil enhancement will depend on the thickness and nature of the soil added. The installation of underground aeration systems has often been recommended for large soil additions but <a href="https://acorn.mortonarb.org/Detail/objects/56059">studies on their effectiveness are inconclusive</a>.</p>
<p>Reducing the impacts of construction requires protective measures to be planned in advance, and close supervision of the construction site. Several standards and guides exist, but their recommendations sometimes diverge. Those measures are often based on a limited number of well-documented studies. Additional research efforts are still needed to validate them and propose new ones.</p><img src="https://counter.theconversation.com/content/154540/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jean-Claude Ruel receives funding from the Québec City municipal government. </span></em></p>To protect urban trees, it’s important to reduce the impact from construction. Advance planning and close supervision can help.Jean-Claude Ruel, professeur en sylviculture et en foresterie urbaine, Université LavalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1541142021-02-01T15:35:29Z2021-02-01T15:35:29ZWhy keeping one mature street tree is far better for humans and nature than planting lots of new ones<p>Thanks to <a href="https://www.jstor.org/stable/j.ctt1s47548">Victorian street planners</a>, many British streets were designed to be full of big trees and, with <a href="https://www.statista.com/statistics/984702/urban-and-rural-population-of-the-uk/">84% of the population living in urban areas</a>, most people are more likely to encounter trees in the streets than they are in forests. </p>
<p>The UK is one of the least densely wooded countries in Europe (at 13% coverage compared to the EU <a href="https://www.forestresearch.gov.uk/tools-and-resources/statistics/forestry-statistics/forestry-statistics-2018/international-forestry/forest-cover-international-comparisons/">average of 38%</a>) and, as such, its street trees are even more valuable. </p>
<p>This became all too clear as the UK first entered lockdown in spring 2020, when many people spent more time on their local streets and in parks. Online tree app Tree Talk <a href="https://www.theguardian.com/environment/2020/jun/05/tree-mapping-app-blossoms-as-city-dwellers-seek-out-nature-in-lockdown-aoe">saw a 50-fold increase</a> in users as people fell in love with their local “street trees”. </p>
<p>They were quite right to do so. The wood of street trees <a href="https://www.woodlandtrust.org.uk/media/1702/benefits-of-trees-outside-woods.pdf">stores carbon</a>, while their roots and crowns <a href="https://www.brebookshop.com/samples/326911.pdf">support wildlife</a> and slow rainfall, <a href="https://www.cityoftrees.org.uk/news/pioneering-street-tree-research-project-could-hold-answer-urban-flooding">reducing urban flooding</a>. Transpiration and shade from their canopies <a href="https://www.forestresearch.gov.uk/documents/7125/FCRN037.pdf">reduces temperatures</a> in heatwaves, while pollution-trapping leaves <a href="https://jech.bmj.com/content/62/7/647.short">lower the prevalence of asthma</a>. </p>
<p>If these ecosystem services weren’t enough, having trees on our streets reduces <a href="https://blogs.lse.ac.uk/usappblog/2015/11/20/trees-a-new-partner-in-the-fight-against-urban-crime/#Author">crime rates</a> and <a href="https://www.nature.com/articles/srep11610">improves mental health and wellbeing</a>. One mature street tree can have a <a href="https://www.tandfonline.com/doi/full/10.1080/03071375.2018.1454077">net ecosystem service value</a> of thousands of pounds. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A row of large trees along a street." src="https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/381365/original/file-20210129-13-181xmu1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Good for both the environment and human wellbeing.</span>
<span class="attribution"><span class="source">Willy Barton/shutterstock</span></span>
</figcaption>
</figure>
<h2>Big trees are being felled</h2>
<p>Sadly, the UK has an unhealthy street tree-felling habit. Up to <a href="https://inews.co.uk/news/environment/revealed-suburban-trees-felled-rate-58-day-56159">60 trees per day</a> are chopped down to make way for buildings and infrastructure, such as roads or sewers. Felling rates could also rise as development accelerates and governments <a href="https://www.theguardian.com/environment/2020/aug/06/planning-reforms-will-damage-uk-nature-environmentalists-warn">relax planning rules</a> to aid post-pandemic economic recovery. </p>
<p>It is larger street trees which are most often the <a href="https://www.woodlandtrust.org.uk/blog/2020/10/happy-man-tree/">victims of development</a> because they are a challenge for city planners. </p>
<p>Large species like London planes, beech and oak need expensive, carefully engineered tree pits to help them grow safely surrounded by concrete and to prevent their roots from pushing up pavements. Such costs are more than offset, though, when we value nature – a single mature oak produces <a href="https://www.theguardian.com/travel/2020/oct/10/into-the-woods-in-search-of-britains-ancient-oak-trees-wiltshire#:%7E:text=A%2520single%2520400%252Dyear%252Dold,litres%2520of%2520oxygen%2520a%2520year.">hundreds of thousands of litres of oxygen per year</a> and supports thousands of species of birds, insects, lichen and fungus.</p>
<p>Residents and councils regularly clash over urban tree-felling. However, when Sheffield City Council entered into a contractor programme a few years ago, which felled more than 5,000 trees, the protests <a href="https://www.nytimes.com/2018/03/13/world/europe/uk-sheffield-trees.html">made international news</a>. </p>
<p>Councils are wary of street tree issues now, and often try to manage PR by claiming felling is mitigated by planting several smaller trees to replace each large one removed. When local authorities like Swansea City Council claim development will result in “<a href="https://www.swansea.gov.uk/MoreTrees">more trees</a>” they are of course right, but it is not the full story.</p>
<p>Just as any child would understand they were being ripped off if given a 2p piece and a 1p piece to replace a pound coin, removing large species trees and replacing them with small ones results in a net loss of ecosystem services. </p>
<p><a href="https://twitter.com/wtjoecoles?lang=en">Joe Coles</a>, the urban tree campaigner responsible for conservation charity Woodland Trust’s work in Sheffield, describes this as a form of greenwashing. “If we value green infrastructure to the same level as grey then large street trees will become far too valuable to lose”, he tells me. “Until there is acceptance that large trees, taking decades to reach maturity, have significant value – a fact based on scientific evidence – we will continue to see spurious but convenient assertions that higher numbers of small replacement trees are adequate compensation to facilitate development.”</p>
<p>Size really matters with trees. The annual net ecological benefit of planting a large species tree is <a href="https://www.brebookshop.com/samples/326911.pdf">92% greater</a> than planting a small one. Mature street trees do everything from <a href="http://depts.washington.edu/hhwb/Thm_StressPhysiology.html">having a positive effect on infant birth weight</a> in lower socio-economic demographics, to increasing <a href="https://journals.sagepub.com/doi/10.1177/00139160121972846">resilience to major life events</a> among people who live within sight of them. Consumers spend more on <a href="http://www.naturewithin.info/New/2014.City-Trees-and-Consumer-Response.Bk%2520Chapt.Wolf.pdf">streets that are lined with large trees</a>. </p>
<p>Large street trees are the most valuable green infrastructure asset cities have and when that value is overlooked, disasters happen. Even winning the UK’s “tree of the year” competition in 2020 couldn’t save Hackney’s <a href="https://www.woodlandtrust.org.uk/blog/2020/10/happy-man-tree/">Happy Man Tree</a> from being felled in 2021 to make way for a new housing development. </p>
<p>More than 25,000 petitioners objected to the removal of the healthy, 150-year-old London plane, with even the developers <a href="https://www.hackneycitizen.co.uk/2020/09/10/happy-man-tree-felled-councillors-accept-loss-heavy-heart/">admitting it would have been avoidable</a> had earlier consultation taken place.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1346370694364467201"}"></div></p>
<p>There is hope for change in the form of <a href="https://www.woodlandtrust.org.uk/publications/2016/07/local-authority-tree-strategies/">tree strategies</a> which set policies to guide development and planning and which require community consultation. They are a <a href="https://www.forestresearch.gov.uk/research/analysis-and-development-local-authority-tree-strategies/">valuable tool</a> for stewarding urban trees for future generations. </p>
<p>Bristol, perhaps the UK’s flagship green city, has adopted a <a href="https://www.bristol.gov.uk/documents/20182/34520/SPD%2520Final%2520Doc%2520Dec2012.pdf/daf75908-50fd-4138-afed-770310a6a431">tree replacement standard</a> to ensure planting new trees meaningfully offsets the loss of carbon and ecosystem services where felling cannot be avoided. Tree replacement standards ensure an adequate number of trees are planted to offset each lost and quantifies the financial contribution developers must make if they choose to fell. </p>
<p>Even tree-war epicentre Sheffield has moved forwards, bringing people together to develop a new <a href="https://www.sheffieldtreeweek.co.uk/new-page-4">street tree partnership working strategy</a> that values street trees for the benefits they bring to people, the city and the environment. </p>
<p>These strategies allow local authorities to mandate that developers value tree size and the total canopy cover in a city. The idea is to prevent the use of “stem counts” to hide the removal of large trees and their replacement with smaller trees that are less valuable in terms of carbon storage, ecosystem services and even human wellbeing.</p><img src="https://counter.theconversation.com/content/154114/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mary Gagen is a member of Swansea Tree Forum. </span></em></p>Greenwashing spin is often used to justify chopping down mature street trees.Mary Gagen, Professor Of Physical Geography, Swansea UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1447512020-08-19T14:04:05Z2020-08-19T14:04:05ZHow racism and classism affect natural ecosystems<figure><img src="https://images.theconversation.com/files/353641/original/file-20200819-42976-16z1dxs.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">Donatas Dabravolskas / shutterstock</span></span></figcaption></figure><p>Structural racism and classism could profoundly affect the existence of flora and fauna in our cities, according to a recent landmark publication in the academic journal <a href="https://science.sciencemag.org/content/early/2020/08/12/science.aay4497">Science</a>. </p>
<p>Urban ecosystems are made up of lots of complex interactions between social and natural systems. The result is a variety of environmental conditions that wouldn’t exist without humans, such as industrial pollution, habitats lacking in biodiversity, and localised climate change in the form of <a href="https://www.sciencedirect.com/science/article/pii/S0169204619311508?casa_token=BMaAr2q2nsIAAAAA:YvP4XOcA-AXPQEndEo6h1gauoGgQjLb2bjA1vKquYclzxoCk6Rmb51KH7PIsZ3Sf9Yi5_I4FhSFt">urban heat island effects</a>. </p>
<p>But these conditions can be unevenly distributed as a result of structural <a href="https://science.sciencemag.org/content/early/2020/08/12/science.aay4497">racism and classism</a>. The disproportionate exposure of Black, Asian and minority ethic (BAME) and poor communities to unfavourable environmental conditions is referred to as “<a href="https://ehp.niehs.nih.gov/doi/pdf/10.1289/ehp.02110s2161#:%7E:text=Environmental%2520injustice%2520can%2520be%2520defined,laws%252C%2520regulations%252C%2520governmental%2520programs%252C">environmental injustice</a>”. This concept also highlights the variability in fairness and respect for social and ecological systems, which could have profound effects on both human and non-human organisms.</p>
<p>The lead author of the new study, Christopher J. Schell of the University of Washington, points out that neighbourhood wealth <a href="https://science.sciencemag.org/content/early/2020/08/12/science.aay4497">has been associated with urban biodiversity</a> patterns – that is, wealthier areas often have more diverse plants. This process has been referred to as the <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2018.0082">luxury effect</a>. Affluent urban dwellers typically have access to <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1002/pan3.10082">better green spaces</a> and more <a href="https://www.fs.usda.gov/treesearch/pubs/58297">vegetation cover</a> and <a href="https://www.frontiersin.org/articles/10.3389/fevo.2020.00085/full">diversity</a>. </p>
<p>The luxury effect may also affect animals. For example, one study found that household income predicted a higher <a href="https://www.biorxiv.org/content/10.1101/2020.04.23.058537v1.full">abundance of migratory birds</a>, and another found that invertebrate diversity was greater in <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2016.0322">high-income neighbourhoods</a>. Furthermore, industrial pollution may disproportionately <a href="https://www.ncbi.nlm.nih.gov/books/NBK219328/">disrupt natural ecosystems</a> in low-income neighbourhoods, and highly-degraded habitats (for instance where natural land has been cleared) can favour <a href="https://www.sciencedirect.com/science/article/pii/S0160412018331386">opportunistic</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/17347336/">pathogenic</a> microbes and <a href="https://www.nature.com/articles/s41586-020-2562-8">wildlife hosts of human-associated pathogens</a>.</p>
<p>In many cities around the world, environmental injustice has been dictated by structural racism. For example, in the last century, racial segregation in US cities led to extreme disparities in the quality and accessibility of health-promoting natural environments. Indeed, the legacy of underlying policies like these may still determine the very existence of the birds, the bees, the microbes and the trees in our urban areas. Connectivity between parks and other urban vegetation can even <a href="https://science.sciencemag.org/content/early/2020/08/12/science.aay4497">drive evolution</a> by influencing the flow of genes between habitats.</p>
<p>Social inequality also affects biodiversity in less obvious ways. For example, unequal distribution of natural habitats could have important cascading effects on the relationship between humans and their natural surroundings. Urban residents growing up in less biodiverse environments may be denied the opportunity to cultivate a much <a href="https://www.sciencedirect.com/science/article/pii/S0169204616302729">deeper relationship with the rest of the natural world</a>. This severed connection can mean missing out on beneficial interactions with a <a href="https://www.mdpi.com/2078-1547/9/2/40/htm">rich consortium of microbes</a> or the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5981243/#:%7E:text=Findings%2520suggest%2520that%2520visiting%2520natural,setting%2520or%2520indoor%2520exercise%2520facility.">psychologically restorative properties</a> of being out in nature. It could also affect lifestyle choices and inhibit pro-ecological actions such as lobbying for species conservation, recycling, or wildlife-friendly planting. Indeed, social inequality risks the flourishing of the future stewards of our planet – the next generation of biodiversity protectors.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Red macaw parrot in jungle" src="https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/353645/original/file-20200819-25043-18ptyer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Indigenous territories contain much of the world’s biodiversity.</span>
<span class="attribution"><span class="source">Ondrej Prosicky / shutterstock</span></span>
</figcaption>
</figure>
<p>Racism and classism doesn’t only affect biodiversity in cities, of course. For example, it has been reported that <a href="https://www.iucn.org/news/secretariat/201908/iucn-director-generals-statement-international-day-worlds-indigenous-peoples-2019">80% of the world’s forest biodiversity</a> exists within Indigenous peoples’ territories. Indigenous cultures are intricately connected to their local ecosystems, nurtured by millennia of deep reciprocity with the wider natural world. Therefore, the degradation of the environment can lead to cultural erosion and vice versa. The exploitation of Indigenous peoples <a href="https://tobaccocontrol.bmj.com/content/early/2020/05/27/tobaccocontrol-2020-055766.abstract">continues today</a> and <a href="https://heinonline.org/HOL/Page?handle=hein.journals/vlr27&div=42&g_sent=1&casa_token=proBVJXpMSUAAAAA:fWTq6t1AnX32wjLB4Jl-yn-1MUsK4sH8jbW0SZA6pd74jFZ8f0sPPvnDsJRcJV-AKbE32qL64p4&collection=journals">colonialism is still rife</a>. This threatens not only the Indigenous communities themselves, but also the rich biodiversity they protect. Strides have been made to protect the rights and livelihoods of Indigenous peoples but considerably more can and must be achieved.</p>
<p>The interrelated nature of systemic racism and classism and ecological change means that structural social issues are also highly relevant to conservationists. Therefore, we must articulate and convey their importance in these fields and prioritise greater integration between social scientists and ecologists. Acting now to dismantle socio-ecological oppression and avoid further ill-fated outcomes is vital. As Christopher Schell, the lead author of the new study in Science, <a href="https://science.sciencemag.org/content/early/2020/08/12/science.aay4497">concludes</a>: “The decisions we make now will dictate our environmental reality for centuries to come.”</p><img src="https://counter.theconversation.com/content/144751/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jake M. Robinson receives funding for his PhD from the Economic and Social Research Council (ESRC). He is affiliated with inVIVO Planetary Health, the Healthy Urban Microbiome Initiative, and Greener Practice. Jake is also working with the Centric Lab (Twitter: @TheCentricLab). Their aim is to improve the quality and accessibility of healthy urban environments through strategies such as Microbiome-Inspired Green Infrastructure (MIGI).</span></em></p>Scientists find inequality between humans also harms the birds, the bees, the microbes and the trees.Jake M Robinson, PhD Researcher, Department of Landscape, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1341972020-04-07T11:49:43Z2020-04-07T11:49:43ZHow to discover the wildlife wonders of your own garden<figure><img src="https://images.theconversation.com/files/322524/original/file-20200324-155624-15vmnh0.jpg?ixlib=rb-1.1.0&rect=382%2C16%2C1250%2C1134&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Blue tits are regulars at the garden bird feeder.</span> <span class="attribution"><span class="source">Mark Fellowes</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Being stuck at home during lockdown could be a golden opportunity to reset your connection with nature. If you’re lucky, you’ll still have access to a garden. Over <a href="http://www.wlgf.org/The%20garden%20Resource.pdf">85%</a> of homes in the UK have one, but if you don’t, hopefully there’s a park nearby.</p>
<p>Gardens and parks provide a tremendous resource for biodiversity, and they’re perfect places to observe and reflect on nature. Start with birds. Globally, around a <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2013.3330">fifth</a> of all bird species are found in urban areas, and they are the entry drug to a world of natural history wonder. Take time to just sit, watch and learn. </p>
<p>Almost <a href="https://bioone.org/journals/Acta-Ornithologica/volume-50/issue-1/00016454AO2015.50.1.006/Wild-Bird-Feeding-in-an-Urban-Area--Intensity-Economics/10.3161/00016454AO2015.50.1.006.full">half</a> of UK households feed birds at some point, and they spend around <a href="https://www.bto.org/press-releases/boom-time-britains-bird-feeders">£250 million</a> doing this each year. It’s not just blue tits and robins either. In Reading, we found that around <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ibi.12237">one in 20 households</a> have enticed red kites into gardens with offerings of <a href="https://www.tandfonline.com/doi/full/10.1080/00063657.2014.885491">meat</a>, bringing a bird of prey that was once almost extinct into the heart of British domestic life.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/326075/original/file-20200407-74220-vtkgmi.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">Coming to a garden near you? A red kite in full flight.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/red-kite-milvus-single-bird-flight-145394485">Erni/Shutterstock</a></span>
</figcaption>
</figure>
<p>Most of us learn the names of common species but why stop there? Citizen scientists collecting data are <a href="https://www.bto.org/our-science/projects/gbw">often central to research</a>. Indoor bird watchers have helped reveal the inner lives of garden birds, and there are <a href="https://www.bto.org/our-science/projects/gbw/taking-part">ample opportunities</a> for budding urban naturalists to do the same for butterflies, hedgehogs, toads and frogs. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/324977/original/file-20200402-74854-11qp9xu.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">Inspect any wet patches or ponds for frogs and toads.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/garden-frog-sticking-head-out-pond-1446252734">Paul Steven/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Spring into nature</h2>
<p>Early spring is a very good time to start. <a href="https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/bird-a-z/chiffchaff/">Chiffchaffs</a>, among the first spring migrants to the UK, have arrived from southern Europe, and the peak bird migration period is about to begin. The earliest butterflies have emerged. The sulphur yellow <a href="https://butterfly-conservation.org/butterflies/brimstone">brimstone</a> is perhaps easiest to spot as it patrols gardens, while queen bumblebees busy themselves with nest building. The dawn chorus is building, and the <a href="https://www.independent.co.uk/life-style/gadgets-and-tech/news/coronavirus-lockdown-london-citymapper-app-traffic-data-a9434841.html">sparse morning traffic</a> means that blackbird, great tit and robin songs can be better heard. Wood pigeons and collared doves are collecting nesting material and blue tits are exploring nest boxes. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coronavirus-what-the-lockdown-could-mean-for-urban-wildlife-134918">Coronavirus: what the lockdown could mean for urban wildlife</a>
</strong>
</em>
</p>
<hr>
<p>If you can get out, why not tend your garden so that it benefits wildlife? A <a href="https://www.sciencedirect.com/science/article/pii/S2211335516301401">report</a> published in 2017 suggested that gardening helped reduce symptoms of stress, anxiety and depression. Recent <a href="https://www.wildlifetrusts.org/sites/default/files/2019-09/SROI%20Report%20FINAL%20-%20DIGITAL.pdf">research</a> suggested that for every £1 spent on promoting contact with nature for people suffering from mental health issues, there was a social return valued at almost £7. An interest in nature pays dividends.</p>
<p>But it is not just adults who benefit from immersion in nature. Younger people are increasingly disconnected from nature, with one 2002 <a href="https://science.sciencemag.org/content/295/5564/2367.2">study</a> showing that children could identify more Pokémon than local wildlife. Children with a greater connection with nature tend to be <a href="https://www.frontiersin.org/articles/10.3389/fpsyg.2020.00276/full">happier</a>. Encourage an interest in nature among children and learn together.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/324980/original/file-20200402-74904-ddcqmk.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">Now is the perfect time to get to know your garden visitors better.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/little-girl-examining-batterfies-on-flower-461714752">NadyaEugene/Shutterstock</a></span>
</figcaption>
</figure>
<p>There are many questions we could ask ourselves to better understand how our own lives interact with the environment. Are our <a href="https://academic.oup.com/jue/article/3/1/jux014/4710340">pet cats</a> taking in the sun, or hunting? Where are the <a href="https://www.rspb.org.uk/our-work/conservation/projects/causes-of-population-decline-of-urban-house-sparrows/">house sparrows</a>, and why are they less common? How can we encourage them back? How does urban noise affect <a href="https://academic.oup.com/beheco/article/27/1/332/1744993">bird song</a>?</p>
<p>Keep going – some of the greatest insights into animal behaviour have come from watching garden birds. British biologist <a href="https://britishbirds.co.uk/article/life-david-lack-father-evolutionary-ecology/">David Lack’s</a> seminal 1940s studies of <a href="https://landlinesproject.wordpress.com/2018/12/10/david-lack-and-the-life-of-the-robin/">robins</a> showed how their territorial aggression can be triggered by a golf ball sized clump of red material. <a href="https://www.zoo.cam.ac.uk/directory/nick-davies">Nick Davies’</a> work on dunnocks (an often overlooked garden bird) in Cambridge University’s Botanic Garden revealed their fluid relationships, where anything goes, from monogamy to polyandry and polygyny. Clearly there is much to learn from the species we tend to overlook.</p>
<p>We increasingly experience the natural world through a glass, darkly. <a href="https://advances.sciencemag.org/content/5/7/eaax0903">Study after study</a> promotes the physical and emotional benefits of engaging with the natural world. At the very least, gaze out the window. Embrace the moment to connect with a different pace of life. Breathe. During this lockdown, you are prescribed a dose of garden nature, taken daily, as needed. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/make-your-garden-frog-friendly-amphibians-are-in-decline-thanks-to-dry-ponds-99057">Make your garden frog friendly – amphibians are in decline thanks to dry ponds</a>
</strong>
</em>
</p>
<hr>
<h2>Top tips</h2>
<ul>
<li><p>If you have bird feeders, observe and record the number of bird species (there are <a href="https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/identify-a-bird/">online guides</a> that can help) on the different feeders. Try to track when they feed and for how long. You can easily build a nature diary that can be shared online too. If you don’t have bird feeders then simply watch what’s flying overhead – I spotted a hundred pink-footed geese over my garden.</p></li>
<li><p>When darkness falls, try night-watching for hedgehogs, foxes, badgers, deer, bats and owls. The first three can easily be enticed down the garden path with a little cat or dog food. Daytime grey squirrels may be non-natives but they are still entertaining and easy to spot. </p></li>
<li><p>More exciting still, if you have access to remote cameras then you can bring close encounters with nature indoors. But even if you don’t have a garden or local park, you can watch live footage of wildlife from your own home - try <a href="https://www.wildlifetrusts.org/webcams">the Wildlife Trusts</a> and <a href="https://www.rspb.org.uk/get-involved/activities/birdwatch/webcam/">the RSPB</a>. You can even install a nest box cam to watch small birds like blue tits.</p></li>
<li><p>Get hold of some easy-to-grow flower seeds. With these, children can see springtime nature first hand. If you can’t obtain seeds then carefully transplant soil with young seedlings from the garden to a flowerpot. Even a few handfuls of garden soil, if kept moist in a pot or maybe a jam jar, will soon produce seedlings, fungi and mini beasts – just the stuff to keep young minds active.</p></li>
</ul><img src="https://counter.theconversation.com/content/134197/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Fellowes received relevant funding from UK research councils and charities. </span></em></p><p class="fine-print"><em><span>Ian D. Rotherham receives funding from government agencies and research councils</span></em></p>Domestic gardens offer an oasis for urban wildlife, and are a sight for sore eyes during lockdown.Mark Fellowes, Professor of Ecology, University of ReadingIan D. Rotherham, Professor of Environmental Geography and Reader in Tourism and Environmental Change, Sheffield Hallam UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1349182020-04-03T10:47:11Z2020-04-03T10:47:11ZCoronavirus: what the lockdown could mean for urban wildlife<figure><img src="https://images.theconversation.com/files/325040/original/file-20200402-74869-1osy43a.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C6000%2C3375&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">'Today, the pond. Tomorrow, the world!'</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/fiPnthzHOdc">Patrick Robert Doyle/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>As quarantine measures take hold across the world, our towns and cities are falling silent. With most people indoors, the usual din of human voices and traffic is being replaced by an eerie, empty calm. The wildlife we share our concrete jungles with are noticing, and responding.</p>
<p>You’ve probably seen posts on social media about animals being more visible in urban centres. Animals that live in cities or on their outskirts are exploring the empty streets, like the <a href="https://inews.co.uk/news/environment/goats-llandudno-wales-town-coronavirus-uk-lockdown-wildlife-2523916">Kashmiri goats in Llandudno, Wales</a>. Others that would normally only venture out at night are becoming bolder and exploring during the daytime, like the <a href="https://www.elnacional.cat/es/sociedad/coronavirus-jabali-pasea-calles-barcelona_482589_102.html">wild boar in Barcelona, Spain</a>. </p>
<p>Our new habits are altering the urban environment in ways that are likely to be both positive and negative for nature. So which species are likely to prosper and which are likely to struggle?</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1244346150767005697"}"></div></p>
<h2>Hooray for hedgehogs</h2>
<p>It’s important to note some species may be unaffected by the lockdown. As it coincides with spring in the northern hemisphere, trees will still bud and flower and frogs will continue to fill garden ponds with frog spawn. But other species will be noticing our absence. </p>
<p>The way we affect wildlife is complex, and some of the changes that we’ll see are hard to predict, but we can make some assumptions. In the UK, hedgehogs are our most <a href="https://www.rsb.org.uk/news/14-news/1649-hedgehog-wins-favourite-uk-mammal-poll">popular mammal</a>, but their numbers are in rapid decline. There are many reasons for this, but many die on roads after being hit by cars. With people being asked to only make essential journeys, we are already seeing <a href="https://www.independent.co.uk/life-style/gadgets-and-tech/news/coronavirus-lockdown-london-citymapper-app-traffic-data-a9434841.html">reduced road traffic</a>. Our spiny friends will have just emerged from hibernation and will no doubt be grateful for the change. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/325043/original/file-20200402-74874-70nqzn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The lockdown could be well timed for hedgehogs emerging from hibernation.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hedgehog-on-road-682603207">Besarab Serhii/Shutterstock</a></span>
</figcaption>
</figure>
<p>Cities are also noisy places, and the noise affects how different species communicate with each other. Birds have to sing louder and at a higher pitch than their rural counterparts, which <a href="https://academic.oup.com/beheco/article/27/1/332/1744993">affects the perceived quality of their songs</a>. With reduced traffic noise, we could see differences in how bats, birds and other animals communicate, perhaps offering better mating opportunities.</p>
<p>School closures may not be ideal for working parents, but many will use their time to connect with nature in their own backyard. More time spent in gardens (for those lucky enough to have one), perhaps doing activities like making bird feeders, could help <a href="https://www.nature.com/articles/s41467-019-10111-5">encourage nature close to home</a>. There’s been a surge in people taking part in citizen science projects like the <a href="https://www.bigbutterflycount.org/">Big Butterfly Count</a> too. These help scientists to <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.12956">predict the population trends</a> of different species. The British Trust for Ornithology has just made participation in their <a href="https://www.bto.org/our-science/projects/gbw">Garden BirdWatch Project</a> free during the lockdown, so you can connect with wildlife and contribute to important scientific research. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/living-with-rats-involves-understanding-the-city-as-an-ecosystem-118383">Living with rats involves understanding the city as an ecosystem</a>
</strong>
</em>
</p>
<hr>
<h2>Desolation for ducks</h2>
<p>All is not rosy for wildlife. Many species currently rely on food provided by humans. From primates fed by tourists in <a href="https://www.theguardian.com/world/2020/mar/13/fighting-monkeys-highlight-effect-of-coronavirus-on-thailand-tourism">Thailand</a>, to the ducks and geese at local parks which have been closed to the public, many animals may be seeking new sources of food. </p>
<p>In the UK, the bird breeding season has already begun for earlier breeders like robins. Depending on how long restrictions last, many birds could ultimately make bad decisions about where to breed, assuming their carefully chosen spot is always rarely disturbed. This could threaten rarer birds which breed in the UK, such as little terns, as dog walkers and other people flock to beaches once restrictions are lifted, <a href="https://www.theguardian.com/environment/2020/mar/29/uk-wildlife-enjoys-humans-lockdown-but-concerns-raised-over-conservation">potentially trampling and disturbing</a> breeding pairs and their young. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/325045/original/file-20200402-74878-1u2b8oc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A little tern sheltering eggs on an open beach.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/little-tern-young-birdsterna-albifrons-130044731">BOONCHUAY PROMJIAM/Shutterstock</a></span>
</figcaption>
</figure>
<p>Dog walkers also enjoy lowland heathlands, especially those near urban areas such as Chobham Common in Surrey. These rare heaths are home to many rare bird species, like Dartford warblers, which could also see their nests disturbed once humans begin to emerge again in larger numbers. People who are enthralled by wildlife venturing into new areas during lockdown will need to carefully manage their return to the outdoors once restrictions are lifted. </p>
<p>Though some species may face challenges in now silent towns and cities, those species that live alongside us do so because they are so adaptable. They will find new sources of food, and will exploit new opportunities created in our absence. Hopefully this time will allow people to appreciate their local environments more, and find new ways to nurture them once all this is over.</p><img src="https://counter.theconversation.com/content/134918/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>With wild boar in Barcelona and coyotes in San Francisco, the lockdown has transformed concrete jungles worldwide.Becky Thomas, Senior Teaching Fellow in Ecology, Royal Holloway University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1259022019-12-10T13:55:04Z2019-12-10T13:55:04ZSuper rats or sickly rodents? Our war against urban rats could be leading to swift evolutionary changes<figure><img src="https://images.theconversation.com/files/305008/original/file-20191203-67028-48w24m.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3230%2C1953&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cities around the world appear to be harboring increasing numbers of rats, including this one: the inflatable 'Scabby the Rat.'</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/new-york-circa-march-2018-inflatable-1058098781">robert cicchetti/Shutterstock.com</a></span></figcaption></figure><p>It took only a few seconds to spot one. Then another. As I walked into the small park around noon, dozens of rats could be seen scurrying in every direction. They dashed in and out of burrows scattered around the planting beds. They scampered between the safety of shrub cover and the trash bins containing a smorgasbord for them to feed on. They leaped on and off the unoccupied benches encircling the park. The rats of Churchill Square had returned.</p>
<p><a href="http://www.pcconservationlab.org/">I study urban rats</a>, but this tiny park in New York City – at the intersection of Bleecker Street and 6th Avenue in the Greenwich Village section of lower Manhattan – has been a side curiosity of mine. The first time I visited the square, I was just looking for a place to sit for a few minutes during a family excursion.</p>
<p>But an urban ecologist is never really off the clock in the city. I had never seen so many rats in such a small area. Rats are generally nocturnal, so the high activity during daylight probably meant the infestation was severe, which <a href="https://doi.org/10.1371/journal.pntd.0003338">increases the risk of disease transmission to people</a>, <a href="https://www.nytimes.com/2007/11/10/nyregion/10rats.html">damages urban infrastructure</a> and even <a href="https://www.neha.org/node/60389">takes a toll on the mental health of residents</a>. The health, economic and social impacts of rat infestation can be significant.</p>
<h2>Public enemy number one</h2>
<p>While rats – <em>Rattus norvegicus</em>, to be specific – in New York City are not unfamiliar to residents, the Churchill Square rats had become too comfortable. Too established. Too numerous. The following year, rodent bait stations appeared around the park. The familiar black boxes are filled with edible bait containing rodent-killing compounds – rodenticides – that technicians can replace easily on a set schedule. It seemed to work remarkably well; there wasn’t a rat to be seen in Churchill Square during my visits that year.</p>
<p>Yet rats are superbly adapted to forage efficiently, breed often and produce enough progeny to repopulate quickly. So despite the millions of dollars spent annually to combat rats, <a href="https://www.nationalgeographic.com/magazine/2019/04/rats-are-an-inescapable-part-of-city-life/">their numbers appear to be increasing in cities around the world</a>. Most rat populations also <a href="https://doi.org/10.1007/s11252-015-0519-8">rebound quickly</a> after a control campaign ends – a phenomenon known as the “boomerang effect.” Churchill Square is an example of this effect; when the rodenticide stations were removed, the rats returned.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=267&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=267&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=267&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=336&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=336&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305490/original/file-20191205-38997-61v6q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=336&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">There is no shortage of food for rats in New York City.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/rat-walking-on-dump-eat-food-1182872266">Chanawat Phadwichit</a></span>
</figcaption>
</figure>
<h2>They’re back, but they’re different</h2>
<p>While the return of the rats is nearly assured, <a href="https://doi.org/10.3389/fevo.2019.00115">my colleagues and I recently found that the repopulating rats</a> are fundamentally different than the rats present before lethal control was carried out.</p>
<p>For example, an intensive eradication campaign in 2015 in parts of Salvador, Brazil succeeded in cutting the rat population in half, but also led to a <a href="https://urbanevolution-litc.com/2019/06/21/urban-rodent-control-has-big-genetic-impacts-for-rats-in-brazil/">90% reduction in the genetic variation</a> contained within those populations. This included the loss of many of their rarest gene variants. A broad variety of genetic information is thought to be essential for organisms to respond to and remain viable in changing environments. In addition, because the survivors were more closely related to each other, there was also a greater risk of inbreeding among the remaining rats. All of these impacts observed in the Salvador rats constitute what scientists call a genetic bottleneck – and a particularly severe one by any standard. </p>
<p>Genetic bottlenecks are almost always considered in the context of vulnerable populations of conservation concern, not a notorious pest. And the overarching concern is usually long-term survival of the imperiled population. But, pest species like rats, mice, roaches and bed bugs are subject to repeated intentional attempts to deplete their populations through lethal control.</p>
<p>The problem is that there is rarely coordination between pest management staff working with cities or property owners, often with short timelines and insufficient budgets, and scientists interested in tracking the long-term viability of urban pest species.</p>
<p>As the environmental health coordinator for the city of Somerville, Massachusetts, Georgianna Silveira is on the front line of efforts to integrate pest management and policy decisions with a scientific perspective on long-term trends. “Most of these partners are not thinking in the long-term for rat populations,” Silveira notes. “In a practical sense, it’s about putting out fires with quick solutions,” often because there is too little communication among residents, city agencies, pest management professionals and scientists about sustained goals.</p>
<h2>Survival of the fittest super rats…</h2>
<p>For the city rats that survive lethal control, there are two long-term outcomes that our research team is investigating now. The first, and most concerning, is tied closely to the idea of “survival of the fittest.”</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/306030/original/file-20191210-95165-1oygjzm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The next generation of <em>Rattus norvegicus</em>.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/brown-norway-rat-rattus-norvegicus-794944942">M Rose/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>A successful rat control campaign removes many, maybe even most, individuals from the population. The survivors are likely to have certain traits that make them more “fit” – able to avoid the onslaught of exposure to rodenticides, snap traps and other sources of mortality. These survivors then produce more baby rats, which inherit the same helpful traits.</p>
<p>If only the fittest rats make it through the control campaign, the survivors may be even better adapted to take advantage of the high-resource minefield of modern cities, leaving a new population of “super rats” to breed and repopulate. In fact, scientists have <a href="https://doi.org/10.1186/1471-2156-10-4">identified specific versions of some genes</a> that render common rodenticides ineffective. These beneficial gene variants have been observed in some natural populations of rats regularly exposed to these poisons.</p>
<h2>…or evolving into sickly rats</h2>
<p>On the other hand, biologists know that there can be severe negative consequences for populations that lack genetic variation, similar to the risks of inbreeding in people.</p>
<p><a href="https://doi.org/10.3389/fevo.2019.00115">Our data from Salvador</a> suggests that rats can lose most of their genetic variation very quickly during a lethal control campaign. This variation is the key by which species can respond to changing environments through natural selection. And city environments can change rapidly. </p>
<p>So the second long-term outcome for rats subjected to repeated control programs could be a gradual reduction in survival, reproduction and other traits related to evolutionary fitness. This was observed in crows, <a href="https://doi.org/10.1111/mec.14866">where inbreeding was associated with lower survival</a> and weaker immune function. Progressively weaker, more sickly rats is certainly the preferred scenario when dealing with persistent rat infestation.</p>
<p>So what will happen to the rats of Churchill Square, Salvador and other places where they are frequently targeted for lethal control? To understand if city rats are evolving toward the “super” or “sickly” set of traits, our research team is studying populations before and after rat control campaigns to determine how survival, reproduction and other beneficial traits change during intense control campaigns.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305691/original/file-20191206-90603-pwwv21.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">Jonathan Richardson weighs a rat as part of a study in New York City.</span>
<span class="attribution"><span class="source">Jonathan Richardson</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>But it is immensely challenging to study these aspects of rat biology in wild populations, especially in urban environments. Genetic insights may provide the most practical way to assess the impacts of control efforts, including a way to measure these impacts <a href="https://doi.org/10.1098/rspb.2018.0245">in a standardized way for cities around the world</a>. Regardless, we know that urban rat control needs to progress beyond just trying to poison them.</p>
<p>Comprehensive rodent control will need to focus on long-term and sustainable goals, reducing populations to tolerable numbers using varied tools like rodenticide, <a href="https://www.marketplace.org/2019/05/23/new-york-city-turns-to-dry-ice-to-control-its-rat-population/">dry ice</a> and even <a href="https://www.chicagotribune.com/news/ct-rodent-control-bait-box-met-20170725-story.html">applying contraceptives to reduce fertility</a>. And of course the low-tech – yet most effective – approach of reducing trash availability and installation of <a href="https://www.washingtonpost.com/graphics/2018/local/rat-calls/">rodent-proof garbage cans</a> must be included. Meanwhile, research will shed light onto what effect all of this money and effort is having on urban pests – is it eroding their viability, or turning the gears of evolution to create unintended super organisms?</p>
<p>[ <em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&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/125902/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jonathan Richardson receives funding from the National Science Foundation. </span></em></p>Cities often embark upon drastic and expensive eradication campaigns designed to rapidly rid the city of pests like rats. But are the surviving rats stronger or weaker than before?Jonathan Richardson, Assistant Professor of Biology, University of RichmondLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1253982019-10-22T15:01:05Z2019-10-22T15:01:05ZFilm about Cape Town is being used to raise awareness, and to ask wider questions<figure><img src="https://images.theconversation.com/files/298102/original/file-20191022-120204-m2qoue.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Shutterstock</span> </figcaption></figure><p>Academics have increasingly used video and other electronic methods to collect data and capture reflections from participants. But, until recently, it’s been less common to use film as way of disseminating the results of research. That’s beginning to change.</p>
<p>Film can be a powerful way to share research findings with a broad audience. This is particularly true when academics are <a>combining</a>) the traditions of ethnography, documentary filmmaking, and storytelling.</p>
<p>Film and cinema are increasingly being used in <a href="https://www.situatedecologies.net/archives/portfolio/crosscuts-the-annual-stockholm-environmental-humanities-festival-for-film-text">environmental humanities</a> to complement – or challenge – text-based research. The filmmakers in the arts, sciences and humanities see potential in using the moving images within political philosophy, environmental politics, postcolonial studies, human geography, urban ecology, postcolonial studies, design and literature.</p>
<p>An example of this is the film <a href="https://vimeo.com/256624115">One Table Two Elephants</a>. It is a cinematic ethnography <a href="https://vimeo.com/256624115">created</a> by two Swedish researchers and filmmakers Jacob von Heland and Henrik Ernstson. Based on years of research in Cape Town, it was filmed in 2015 as part of a <a href="https://www.researchgate.net/project/WOK-UE-Ways-of-Knowing-Urban-Ecologies">longer-term research and film-project</a> . The documentary deals with race, nature and knowledge politics in Cape Town as part of the <a href="http://www.situatedecologies.net/archives/portfolio/ways-of-knowing-the-film">ways of knowing urban ecologies research project</a>. </p>
<figure>
<iframe src="https://player.vimeo.com/video/256624115" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
</figure>
<p>Focusing on the global south, this project sought to critically examine the social, cultural and political dimensions of how resources are managed in rapidly growing urban spaces. It set out to answer and provoke debates about questions of sustainability and equality, including questions about identity and power in the context of a postcolonial city. The creators tried to develop and define visual humanities as a rich register to speak eloquently, forcefully and with texture into environmental questions.</p>
<p>The film is part of a wider project to use film as research in challenging and complementing pen and paper. Following this perspective – and based on the explorative idea to treat film-as-research/research-as-film – the filmmakers use cinematic and audio-visual registers to texture people’s understanding of Cape Town. These range from intimate relations to structural issues. The aim is to move the audience beyond simplistic understandings while providing possibilities to translate what is happening to wider conversations about race, nature, and the city in other places of the world.</p>
<p>The film has <a href="https://www.situatedecologies.net/archives/2047">been nominated for several prizes</a> and screened at film festivals in Copenhagen, Cape Town, Tirana, Nijmegen and Stockholm. It became an amazing learning space for the researchers and highly productive for especially the younger scholars and students that have been involved.</p>
<h2>The film</h2>
<p>Entering the city through its plants and wetlands, the many-layered, painful and liberating history of the city emerges as the film follows how biologists, hip hoppers, and wetland activists each search for ways to craft symbols of unity and cohesion.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=848&fit=crop&dpr=1 600w, https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=848&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=848&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1066&fit=crop&dpr=1 754w, https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1066&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/297934/original/file-20191021-56220-1xqbe0r.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1066&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p>The film starts by following black, hip hop break dancers who are trying to bring in their own cultural roots into modern dancing techniques. It also follows conservation efforts being pursued by white residents of the city. </p>
<p>The documentary is directed towards the general public as well as students and scholars. It brings texture to understanding a city like Cape Town. At the same time it provides possibilities to translate what it’s recording into conversations about other cities and surroundings. </p>
<p>Situated and grounded in lived experiences across a range of groups, this film follows different ways of knowing. It tries to be a vehicle toward difficult yet urgently needed conversations about how race, nature and the city are intertwined in South Africa’s postcolonial world, where history is ever present in subtle and direct ways. </p>
<p>The film is unusual in a number of ways. The material is rich and textured. It is edited without a voice over. This enables it to convey multiple interrelated histories across the city. </p>
<p>The film provides possibilities for non-expert as well as experts to reflect on and deliberate over how a city and its environments can be known.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=734&fit=crop&dpr=1 600w, https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=734&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=734&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=922&fit=crop&dpr=1 754w, https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=922&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/298105/original/file-20191022-28129-wc1b9a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=922&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A flyer to advertise a screening of the film.</span>
</figcaption>
</figure>
<h2>Lessons learnt</h2>
<p>The film doesn’t attempt to formulate a coherent theory. Rather, it should be treated as an intellectual investigation that opens up the space to unknown territory – the inter-relationship between the creators of the movie and its subject matter. In this way, it can open the discussion and sketch possible lines of future research. </p>
<p>By developing in-depth studies in Cape Town, South Africa, a rapidly growing city shaped by its colonial and apartheid past and highly unequal, culturally diverse and grappling with resource management challenges, the film aims to contrast the local knowledge with the dominant western one. In this way, it explores the politics of urban environmental knowledge in postcolonial cities. It tries to transmit the “knowledge” that is already produced towards a larger audience.</p>
<p><em>One Table Two Elephants (Documentary film, 84 min, 2018), created by Jacob von Heland and Henrik Ernstson.</em></p><img src="https://counter.theconversation.com/content/125398/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Asma Mehan 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>A film about Cape Town’s environmental resources features a cast as diverse as breakdancers and wetland activists - and is being used as a study aid globally.Asma Mehan, Postdoctoral research associate, Universidade do PortoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/833452017-09-17T19:40:23Z2017-09-17T19:40:23ZMore than just drains: recreating living streams through the suburbs<figure><img src="https://images.theconversation.com/files/185575/original/file-20170912-1368-1qg03ny.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A drain carries water but does little else, but imagine how different the neighbourhood would be if the drain could be transformed into a living stream.</span> <span class="attribution"><span class="source">Zoe Myers</span>, <span class="license">Author provided</span></span></figcaption></figure><p><a href="https://theconversation.com/vanishing-australian-backyards-leave-us-vulnerable-to-the-stresses-of-city-life-81479">Lot sizes and backyards are shrinking</a> in Australia at the same time as <a href="https://theconversation.com/density-threatens-liveability-if-we-miss-the-big-picture-of-how-a-city-works-69549">building density is increasing</a>. So we cannot afford to overlook the potential of existing – but neglected – spaces in our suburbs, like drains. </p>
<p>In denser living environments, we <a href="https://research-repository.griffith.edu.au/bitstream/handle/10072/34429/64917_1.pdf?sequence=1">will need new types of green and open space</a> to meet the needs of residents.</p>
<p>One such overlooked space is the urban water drainage system. As part of my research I’m examining the potential of a co-ordinated and integrated network of suburban streams. </p>
<hr>
<p><em><strong>Further reading:</strong> <a href="https://theconversation.com/if-planners-understand-its-cool-to-green-cities-whats-stopping-them-55753">If planners understand it’s cool to green cities, what’s stopping them?</a></em></p>
<hr>
<p>The largest water catchment in the Perth metropolitan area is <a href="http://www.bayswater.wa.gov.au/environment/bayswater-brook">Bayswater Brook</a> (previously called the Bayswater Main Drain). Largely for the purpose of improving water quality, in recent years <a href="https://www.mediastatements.wa.gov.au/Pages/Barnett/2012/11/Bayswater-drain-to-be-transformed.aspx">work</a> has <a href="http://www.abc.net.au/news/2015-01-19/bayswater-wetlands-rejuvenation-to-protect-swan-river-health/6025606">begun</a> to remake drains running through the suburbs into “<a href="https://www.water.wa.gov.au/__data/assets/pdf_file/0015/1716/99300.pdf">living streams</a>”.</p>
<p>Aside from the obvious benefits of <a href="http://www.water.wa.gov.au/__data/assets/pdf_file/0019/1657/84955.pdf">water purification and stormwater management</a>, these networks of suburban streams can be re-imagined as preferred paths through the neighbourhood. </p>
<p>Using established drainage routes capitalises on their existing connections through a suburb. This network could amplify the connections between parks and other green areas, providing a rich soundscape of birds, frogs and insects, and a diversity of sedges, rushes, melaleucas and other vegetation along the banks. </p>
<h2>Look at the big picture</h2>
<p>While the conversion of <a href="http://www.water.wa.gov.au/water-topics/waterways/managing-our-waterways2/urban-waterways-management-and-living-streams">old infrastructure into living streams is not new</a>, it has as-yet-unrealised potential to rehabilitate the large sections of open drainage that run in visible, connected ways through our suburbs. This elevates the idea of a living stream to a multi-layered ecosystem, one that includes multiple drains across the suburb. </p>
<p>The Bayswater Brook <a href="http://www.bayswater.wa.gov.au/cproot/932/2/Bayswater-main-drain.pdf">permanent drainage system</a> runs through the northeastern suburbs of Perth. These drains can be dangerous and public entry to these areas is prohibited out of necessity.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185494/original/file-20170911-1342-1x06nn9.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">Access barriers are unsightly but necessary because the existing drains can be dangerous.</span>
<span class="attribution"><span class="source">Author's own</span></span>
</figcaption>
</figure>
<p>The drains run along the rear of mostly low-density housing, hidden from streets.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=580&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=580&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=580&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=729&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=729&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185489/original/file-20170911-1373-ui5dv9.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=729&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An aerial view of houses backing onto a 90-metre long open drain in Perth.</span>
<span class="attribution"><span class="source">Google Earth</span></span>
</figcaption>
</figure>
<p>Their condition is typically marked by weeds, minimal vegetation and stagnant water. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=335&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=335&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=335&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=421&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=421&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185609/original/file-20170912-11536-k2gph2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=421&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fenced-off areas offer no public benefits to the neighbourhood other than drainage.</span>
<span class="attribution"><span class="source">Zoe Myers</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The sheer number of these open drains across the metropolitan area offers a compelling opportunity to reconceptualise the system as a holistic and integrated network of ecologically restored streams. This requires co-operation between multiple levels of government. </p>
<p>A project by WaterCorp in Western Australia (which manages drainage infrastructure) has begun <a href="https://www.watercorporation.com.au/water-supply/ongoing-works/drainage-for-liveability-program">inviting local governments</a> to submit proposals for use of the green space around drains. These are currently for small portions of the larger network, such as a <a href="https://www.mediastatements.wa.gov.au/Pages/Barnett/2016/09/Drains-fuel-green-community-space-gains.aspx">pop-up park planned for a basin in Morley</a>. </p>
<p>The benefit of doing this in a co-ordinated way – rather than single stream restoration – lies in the possibilities of making these spaces a genuine alternative to the street.</p>
<h2>What are the benefits?</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185584/original/file-20170912-20832-79puyy.jpg?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"></a>
<figcaption>
<span class="caption">Typical drains (above and below) add very little to neighbourhood amenity.</span>
<span class="attribution"><span class="source">Zoe Myers</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185585/original/file-20170912-15801-196l0fc.jpg?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"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Zoe Myers</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>By activating unused, off-limits areas at the back of houses, we can turn public space “inside out”. Providing a sequence of accessible paths creates a new option for pedestrians away from roads and cars, but still with an established, clear route through the suburb. We can have a space that is buffered from traffic noise without the isolation of an empty park segregated from main thoroughfares. </p>
<p>Many studies have convincingly found <a href="http://www.tlu.ee/%7Earro/Happy%20Space%20EKA%202014/blue%20space,%20health%20and%20wellbeing.pdf">connections between the sounds of waterscapes and restorative emotional states and views</a>. Having multiple entry and exit points as the streams thread through the suburbs would heighten the spaces’ usefulness as everyday pathways. Children could walk along the streams to school, or adults could take a short cut to catch the bus to work, maximising this kind of beneficial interaction with water. </p>
<p>Recreating natural habitats would also increase biodiversity and create a multi-sensory environment, as well as a cooler micro-climate. That would make it an even more attractive place to be in hot months. Encouraging a more natural flow of water through the streams would also reduce biting midges and mosquitoes, which thrive in stagnant water. </p>
<hr>
<p><em><strong>Further reading:</strong> <a href="https://theconversation.com/green-for-wellbeing-science-tells-us-how-to-design-urban-spaces-that-heal-us-82437">Green for wellbeing – science tells us how to design urban spaces that heal us</a></em></p>
<hr>
<p>Potentially the most convincing reason for local governments to rehabilitate drains is that living streams increase neighbourhood property values. <a href="http://www.sciencedirect.com/science/article/pii/S2212428416300123">Research has shown</a> the effect is significant. In the Perth suburb of Lynwood, for example, median home values within 200 metres of a wetland
restoration site <a href="https://watersensitivecities.org.au/wp-content/uploads/2016/07/IndustryNote_A1.2_livingstreams.pdf">increased by A$17,000</a> to A$26,000 above
the trend increase for the area. </p>
<p>This in turn can support increased density. High quality nature spaces potentially offset the sacrifice of the usual backyard area, by increasing the number of people with direct access to these spaces.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=467&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=467&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185485/original/file-20170911-1327-1hmpnwq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=467&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Turning an urban drain into a living stream opens up a world of possibilities.</span>
<span class="attribution"><span class="source">Author's original render</span></span>
</figcaption>
</figure>
<p>There is a growing imperative to remove the false choice between designing for people or for nature. Remaking our old infrastructure for many new uses offers multiple benefits to our ecology and well-being. When a drain becomes a living stream it doesn’t just provide a new kind of open space but adds a new dimension to enjoying, and moving through, your suburb.</p><img src="https://counter.theconversation.com/content/83345/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zoe Myers 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>Drains take up precious but inaccessible open space in our cities. Converting these to living streams running through the suburbs could make for healthier places in multiple ways.Zoe Myers, Research Associate, Australian Urban Design Research Centre, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/820242017-08-15T14:09:37Z2017-08-15T14:09:37ZWhy red squirrels are thriving in one corner of Merseyside<figure><img src="https://images.theconversation.com/files/182085/original/file-20170815-29205-5bcb20.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">Phil Kieran / shutterstock</span></span></figcaption></figure><p>By 2050, <a href="http://ow.ly/MpUZ30e73sA">two thirds</a> of the world’s population will live in an urban area. Until recently, we knew little about how wild animals were coping with the growth of all those towns and cities. The field of urban wildlife ecology has since emerged to fill this gap.</p>
<p>Urban ecologists have found some species, like Britain’s <a href="http://ow.ly/XkQb30e73IM">hedgehogs</a>, have struggled to cope. But other species, often called “synurbic”, have proven themselves very adaptable and, in some cases, they can actually live at <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2011.00887.x/abstract">higher densities</a> in cities. </p>
<p>One species capable of modern urban living is the red squirrel. Understanding how they behave in towns and cities, a topic that is relatively unexplored, could help their long-term conservation.</p>
<p>Red squirrels are found in cities right across mainland Europe, for example in <a href="http://ow.ly/iaMw30e73WQ">Finland</a>, <a href="http://www.scoiattologrigio.org/scoiattoli%20-%20european%20red%20squirrels%20urban%20park.pdf">France</a>, and <a href="http://ow.ly/20Jp30e746U">Poland</a>. It is likely they were once also found in many UK towns too. However, Britain’s native squirrel is now a very rare sight, thanks to decades of habitat loss and the introduction of the larger and more competitive grey squirrel from North America.</p>
<h2>A red stronghold</h2>
<p>But one town where the reds haven’t disappeared is Formby, in Merseyside, the study site for my PhD researching the urban ecology of red squirrels. Formby is one of few red squirrel strongholds in England and one of the only remaining urban areas where they can be found at all. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"519839175932379136"}"></div></p>
<p>Red squirrels can easily be spotted in gardens throughout the town. Local residents are passionate about protecting their unusual wildlife, with many of them providing supplemental food and volunteering locally with <a href="https://www.wildlifetrusts.org/news/2017/02/24/vital-volunteers-needed-save-our-last-red-squirrels">conservation organisations</a>. These organisations manage the extensive woodland to the west of the town, where they supply additional food themselves, and employ dedicated “squirrel officers” who help maintain “<a href="https://www.lancswt.org.uk/redsquirrels">grey squirrel-free</a>” habitats.</p>
<p>In addition to the woodland, the town itself contains ideal habitat, with hedgerows and trees lining the roads and gardens, which provide corridors for the squirrels to move through. Urban areas also typically have fewer natural predators, such as buzzards.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/182090/original/file-20170815-28964-6ywrrk.jpg?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"></a>
<figcaption>
<span class="caption">The woods near Formby are famous for their red squirrels.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/fotofrivolity08/13611318394/">Ellie</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Unfortunately, invasive grey squirrels like all these things too and, given the chance, they would colonise the town and displace the reds. However, a combination of grey squirrel control (including protection from their advances on one side by the sea), supplemental feeding, suitable urban green spaces, and careful monitoring by volunteers and rangers have meant that the reds have clung on in Formby, despite greys replacing them elsewhere in the UK. </p>
<p>The longer-term strategy is to manage the area in favour of the reds. This could involve, for example, planting trees which the reds can easily exploit but the greys are less able to, like native conifers and small-seeded broadleaved trees such as birch or ash. Greys instead prefer large-seeded broadleaves, such as oak and beech.</p>
<h2>Urban hazards</h2>
<p>However, there are downsides to living alongside people. For instance, several studies have flagged <a href="http://ow.ly/C6OZ30e74me">road traffic</a> as the biggest cause of squirrel mortality. Despite fewer natural predators, there are higher numbers of pets, such as <a href="http://onlinelibrary.wiley.com/doi/10.1017/S0952836902000134/abstract">cats</a> and dogs, that can injure and even kill squirrels. In addition, some of the trees in the town may be gradually lost as residents landscape their gardens, further fragmenting the remaining habitat.</p>
<p>Even the widespread supplemental feeding could have hidden negative consequences. In Formby, well-meaning residents provide lots of peanuts: one of the squirrels’ favourite foods. Unfortunately, peanuts are low in calcium and alone do not give the required nutrition that a squirrel needs. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/182092/original/file-20170815-28398-1ayvmsu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chomping on a peanut provided by a well-meaning local.</span>
<span class="attribution"><span class="source">Kat Fingland</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>If feeders are not cleaned thoroughly and regularly, this could also contribute to another outbreak of <a href="http://ow.ly/SiNI30e74wz">squirrelpox virus</a> or other diseases. This suggests that residents, who are enthusiastic about feeding the squirrels (and should continue to do so), perhaps need to be provided with more information, such as on what to supply for a varied diet.</p>
<h2>Urban management as a conservation tool</h2>
<p>Much of the research and conservation of red squirrels in the UK is carried out in more rural areas, such as Kielder Forest in Cumbria, often along the interface with the invasive grey squirrel. However, managing urban sites for the benefit of the native reds could be a useful alternative conservation tool, through making the most of the benefits of living alongside people. </p>
<p>For example, local volunteers could act as a free and dedicated workforce for conserving and monitoring the red squirrels, as is the case in Formby. This could be employed in the nearby towns, or even elsewhere in Britain near squirrel strongholds, to hopefully encourage the reds to disperse and reoccupy areas as they become free from greys. This is currently occurring in Wales, with reds crossing over from the island of <a href="https://www.theguardian.com/environment/2016/oct/13/red-squirrels-wales-protected-military-style-strategy-ogwen-valley">Anglesey</a> onto the mainland as rangers remove greys from the area around nearby Bangor.</p>
<p>An urban management plan could also create the opportunity to develop more green spaces and wildlife-friendly gardens. This would benefit all of the local biodiversity, not only squirrels, as well as the people.</p>
<p>This is what my research aims to explore over the next few years: how have red squirrels adapted to urban life, and how do the associated resources and risks affect their ecology. By understanding this, we can hopefully develop a strategy to better protect this charming native species.</p><img src="https://counter.theconversation.com/content/82024/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kathryn Fingland is working closely with the Lancashire Wildlife Trust and National Trust to conduct her PhD research in Formby.</span></em></p>Formby is one of the only remaining urban areas in England where red squirrels can be found at all.Kathryn Fingland, Doctoral Researcher in Wildlife Conservation & Ecology, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/774392017-05-30T12:56:06Z2017-05-30T12:56:06ZHow the red fox adapted to life in our towns and cities<p>Flexible foxes can be found in almost any sort of terrain. Indeed, one species, the red fox or <em>Vulpes vulpes</em>, is the most widely distributed land carnivore of all, ranging from the Arctic to North Africa. And where its rivals stick to the countryside, these foxes have made themselves at home in modern towns and cities. Why is this?</p>
<p>For a start, red foxes are unfussy omnivores. They will eat mice, birds, invertebrates and berries – or your leftover pizza. Our cities are full of potential food for them. </p>
<p>Foxes also benefit from a cat-like agility to navigate around the urban landscape. Their “parkour” abilities mean they can access and exploit more parts of the city than other less agile urban carnivores such as badgers.</p>
<p>No wonder then that foxes have been reported in Britain’s cities since around about the 1930s – and <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099059">my research</a> has shown they’re now found in more or less every town and city in the UK.</p>
<p>Back in 1995 it was estimated that England had <a href="http://jncc.defra.gov.uk/pdf/pub03_areviewofbritishmammalsall.pdf">around 33,000 urban foxes</a> but numbers today will be be higher as they’ve since moved into yet more cities. This is in contrast to the UK’s overall fox population, mostly rural, which has <a href="https://www.bto.org/volunteer-surveys/bbs/latest-results/mammal-monitoring">declined by 34%</a> over the past two decades – and will fall even further <a href="http://www.independent.co.uk/news/uk/politics/theresa-may-fox-hunting-bring-back-ban-repeal-conservative-tories-general-election-rural-vote-a7726506.html">if Theresa May gets her way</a> and repeals the ban on fox hunting.</p>
<p>Many people enjoy the presence of urban foxes and the sense of having genuine wildlife in their gardens. Others however complain about the smell, their poo, or the screaming sounds foxes make when the vixen is calling for a mate during the breeding season.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zk1mAd77Hr4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>It is not uncommon for next door neighbours to have radically different views. Often, the main conflict isn’t between humans and fox – it’s between two humans. </p>
<p>Foxes are known to prey on rats and pigeons and so may help to control pest populations. However they can also spread certain <a href="http://www.thefoxwebsite.net/disease/diseaseother">diseases</a> which can infect humans, so care needs to be taken over contact with fox poo in the garden by people and pets.</p>
<p>Reports of <a href="http://news.bbc.co.uk/1/hi/magazine/8726282.stm">bites to humans</a> are rare, considering the number of people and foxes living cheek by jowl. They usually arise from the <a href="http://www.standard.co.uk/news/london/fox-attacks-man-woman-and-cat-at-their-home-in-south-london-8699892.html">animal being cornered</a> rather than an unprovoked attack, so people shouldn’t try luring them into their houses with food.</p>
<p>Some cities are more fox-friendly than others. As the animals prefer suburban areas to industrial or inner-city areas without gardens, it’s perhaps no surprise that the UK’s highest fox density was recorded in <a href="https://www.theguardian.com/cities/gallery/2017/jan/05/green-space-uk-largest-cities-mapped">relatively leafy Bristol</a> back in the 1990s. (However shortly after this 95% of the city’s foxes were killed by <a href="https://core.ac.uk/download/pdf/17352877.pdf">an outbreak of sarcoptic mange</a>, a contagious skin disease).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/171468/original/file-20170530-16306-1dqmyje.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fun times in fox-friendly Bristol.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/samuir/8430822100/">shrinkin'violet / flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>More recently <a href="https://www.brighton.ac.uk/research-and-enterprise/research/life-health-and-physical-sciences/research-groups/ecosystems-and-environmental-mngmt/urban-mammals.aspx">colleagues and I</a> estimated the suburbs in Brighton average around 12 foxes per km², which contrasts with the human population density of 3,445/km². We are still working on the data, but it looks fox numbers have increased in recently-colonised cities, while things have remained more stable in cities with well-established populations.</p>
<h2>Could the ‘urban fox’ evolve into its own species?</h2>
<p>Foxes still move back and forth between town and country. There is sufficient mixing of the population that would prevent the evolution of a distinct genetically separate “urban fox”. </p>
<p>However, foxes in urban areas may be changing their behaviour to adapt to city life. Previous studies found urban foxes <a href="http://www.wildlifeonline.me.uk/red_fox_diets.html">still mostly eat “natural” food</a> such as rodents, birds and invertebrates. Human-provided food is only a supplementary part of their diet. However, as more and more people provide food for wildlife in their gardens it is likely that the diet and behaviour of urban foxes may shift towards food provided by humans. </p>
<p>Colleagues and I are now looking at how this extra food will affect fox behaviour and movements. Fox behaviour is directly influenced by how humans act towards them. If people encourage close contact then this will drive tolerance to our presence and if people feed the foxes they will develop an association between humans and food. As populations are typically limited by resources, providing food could be supporting unnaturally high fox densities.</p>
<p>However, foxes also self regulate and it is clear that diseases such as mange have some influence on numbers. This also means that culling foxes has little long-term impact on populations.</p>
<p>Certain personality traits or behaviours may also be advantageous when living with humans and exploiting the urban environment. Individuals that are bolder and can solve problems of how to access food quicker are more likely to be more successful in obtaining food, and thus to reproduce. Over time, these traits may be selected for within urban populations, producing smarter and more courageous foxes. On the flip side, those foxes that cannot tolerate humans are unlikely to thrive in cities and will not pass on their traits to the next generation.</p>
<p>Whatever the future holds for urban foxes, cities provide plentiful food and refuges for them – so they’re here to stay. Love them or hate them, these animals have successfully adapted to the habitats we have built around them, and they are one of a few animals that can tolerate and adapt to our changing behaviour.</p><img src="https://counter.theconversation.com/content/77439/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dawn Scott has previously received funding from the Animal Plant and Health Agency. She is affiliated with the British Ecological Society. </span></em></p>These agile and unfussy animals are well-placed to exploit all the food we leave lying around.Dawn Scott, Principal Lecturer in Ecology, University of BrightonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/759572017-04-12T18:01:33Z2017-04-12T18:01:33ZFishing for DNA: Free-floating eDNA identifies presence and abundance of ocean life<figure><img src="https://images.theconversation.com/files/164726/original/image-20170410-31882-15i73ly.jpg?ixlib=rb-1.1.0&rect=12%2C84%2C813%2C449&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Fish leave bits of DNA behind that researchers can collect.</span> <span class="attribution"><span class="source">Mark Stoeckle/Diane Rome Peebles images</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Ocean life is largely hidden from view. Monitoring what lives where is costly – typically requiring big boats, big nets, skilled personnel and plenty of time. An emerging technology using what’s called environmental DNA gets around some of those limitations, providing a quick, affordable way to figure out what’s present beneath the water’s surface. </p>
<p>Fish and other animals shed DNA into the water, in the form of cells, secretions or excreta. About 10 years ago, researchers in Europe first demonstrated that small volumes of pond water contained enough <a href="https://dx.doi.org/10.1098/rsbl.2008.0118">free-floating DNA to detect resident animals</a>.</p>
<p>Researchers have <a href="https://dx.doi.org/10.1371/journal.pone.0023398">subsequently</a> <a href="https://dx.doi.org/10.1371/journal.pone.0035868">looked for</a> <a href="https://doi.org/10.1016/j.biocon.2014.11.025">aquatic eDNA</a> <a href="https://doi.org/10.1111/1755-0998.12433">in multiple</a> <a href="https://doi.org/10.1016/j.biocon.2014.11.020">freshwater systems</a>, and <a href="https://dx.doi.org/10.1371/journal.pone.0041732">more recently</a> in <a href="https://dx.doi.org/10.1371/journal.pone.0041781">vastly larger</a> and <a href="https://dx.doi.org/10.1371/journal.pone.0086175">more complex</a> <a href="https://doi.org/10.1111/mec.13481">marine</a> <a href="https://dx.doi.org/10.1371/journal.pone.0165252">environments</a>. While the principle of aquatic eDNA is well-established, we’re just beginning to explore its potential for detecting fish and their abundance in particular marine settings. The technology promises many practical and scientific applications, from helping set sustainable fish quotas and evaluating protections for endangered species to assessing the impacts of offshore wind farms.</p>
<h2>Who’s in the Hudson, when?</h2>
<p><a href="https://doi.org/10.1371/journal.pone.0175186">In our new study</a>, <a href="https://phe.rockefeller.edu/barcode/blog/nycnj-aquatic-vertebrate-edna-project/">my colleagues and I</a> tested how well aquatic eDNA could detect fish in the Hudson River estuary surrounding New York City. Despite being the most heavily urbanized estuary in North America, water quality has <a href="http://www.nyc.gov/html/dep/pdf/hwqs2011.pdf">improved dramatically</a> over the past decades, and the estuary has partly recovered its role as essential habitat for many fish species. The improved health of local waters is highlighted by the now <a href="https://www.nytimes.com/2016/07/10/nyregion/the-great-new-york-whale-census.html">regular fall appearance of humpback whales</a> feeding on large schools of <a href="http://discovermagazine.com/2001/sep/featfish">Atlantic menhaden</a> at the borders of New York harbor, within site of the Empire State Building. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=751&fit=crop&dpr=1 600w, https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=751&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=751&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=943&fit=crop&dpr=1 754w, https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=943&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/164947/original/image-20170411-26730-1vpceyd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=943&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Preparing to hurl the collecting bucket into the river.</span>
<span class="attribution"><span class="source">Mark Stoeckle</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Our study is the first recording of spring migration of ocean fish by conducting DNA tests on water samples. We collected one liter (about a quart) water samples weekly at two city sites from January to July 2016. Because the Manhattan shoreline is armored and elevated, we tossed a bucket on a rope into the water. Wintertime samples had little or no fish eDNA. Beginning in April there was a steady increase in fish detected, with about 10 to 15 species per sample by early summer. The eDNA findings largely matched our existing knowledge of fish movements, hard won from decades of traditional seining surveys.</p>
<iframe src="https://datawrapper.dwcdn.net/4bGEP/4/" frameborder="0" allowtransparency="true" allowfullscreen="allowfullscreen" webkitallowfullscreen="webkitallowfullscreen" mozallowfullscreen="mozallowfullscreen" oallowfullscreen="oallowfullscreen" msallowfullscreen="msallowfullscreen" width="100%" height="500"></iframe>
<p>Our results demonstrate the “Goldilocks” quality of aquatic eDNA – it seems to last just the right amount of time to be useful. If it disappeared too quickly, we wouldn’t be able to detect it. If it lasted for too long, we wouldn’t detect seasonal differences and would likely find DNAs of many freshwater and open ocean species as well as those of local estuary fish. Research suggests <a href="https://doi.org/10.1021/acs.est.6b03114">DNA decays over hours to days</a>, depending on temperature, currents and so on.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=734&fit=crop&dpr=1 600w, https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=734&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=734&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=922&fit=crop&dpr=1 754w, https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=922&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/164948/original/image-20170411-26733-15fdz4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=922&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Fish identified via eDNA in one day’s sample from New York City’s East River.</span>
<span class="attribution"><span class="source">New York State Department of Environmental Conservation: alewife (herring species), striped bass, American eel, mummichog; Massachusetts Department of Fish and Game: black sea bass, bluefish, Atlantic silverside; New Jersey Scuba Diving Association: oyster toadfish; Diane Rome Peeples: Atlantic menhaden, Tautog, Bay anchovy; H. Gervais: conger eel.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Altogether, we obtained eDNAs matching 42 local marine fish species, including most (80 percent) of the locally abundant or common species. In addition, of species that we detected, abundant or common species were more frequently observed than were locally uncommon ones. That the species eDNA detected matched traditional observations of locally common fish in terms of abundance is good news for the method – it supports eDNA as an index of fish numbers. We expect we’ll eventually be able to detect all local species – by collecting larger volumes, at additional sites in the estuary and at different depths. </p>
<p>In addition to local marine species, we also found locally rare or absent species in a few samples. Most were fish we eat – Nile tilapia, Atlantic salmon, European sea bass (“branzino”). We speculate these came from wastewater – even though the Hudson is cleaner, <a href="https://www.riverkeeper.org/wp-content/uploads/2015/06/Riverkeeper_WQReport_2015_Final.pdf">sewage contamination persists</a>. If that is how the DNA got into the estuary in this case, then it might be possible to determine if a community is consuming protected species by testing its wastewater. The remaining exotics we found were freshwater species, surprisingly few given the large, daily freshwater inflows into the saltwater estuary from the Hudson watershed. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/164945/original/image-20170411-26730-11e9w3d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Filtering the estuary water back in the lab.</span>
<span class="attribution"><span class="source">Mark Stoeckle</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Analyzing the naked DNA</h2>
<p>Our protocol uses methods and equipment standard in a molecular biology laboratory, and follows the same procedures used to analyze human microbiomes, for example.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/164946/original/image-20170411-26741-1ns4wwu.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">eDNA and other debris left on the filter after the estuary water passed through.</span>
<span class="attribution"><span class="source">Mark Stoeckle</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>After collection, we run water samples through a small pore size (0.45 micron) filter that traps suspended material, including cells and cell fragments. We extract DNA from the filter, and amplify it using polymerase chain reaction (PCR). PCR is like “xeroxing” a particular DNA sequence, producing enough copies so that it can easily be analyzed.</p>
<p>We targeted mitochondrial DNA – the genetic material within the mitochondria, the organelle that generates the cell’s energy. Mitochondrial DNA is present in much higher concentrations than nuclear DNA, and so easier to detect. It also has regions that are the same in all vertebrates, which makes it easier for us to amplify multiple species.</p>
<p>We tagged each amplified sample, pooled the samples and sent them for next-generation sequencing. Rockefeller University scientist and co-author Zachary Charlop-Powers created the bioinformatic pipeline that assesses sequence quality and generates a list of the unique sequences and “read numbers” in each sample. That’s how many times we detected each unique sequence.</p>
<p>To identify species, each unique sequence is compared to those in the public database GenBank. Our results are consistent with read number being proportional to fish numbers, but more work is needed on the precise relationship of eDNA and fish abundance. For example, some fish may shed more DNA than others. The effects of fish mortality, water temperature, eggs and larval fish versus adult forms could also be at play.</p>
<p>Just like in television crime shows, eDNA identification relies on a comprehensive and accurate database. <a href="https://doi.org/10.1371/journal.pone.0175186">In a pilot study</a>, we identified local species that were missing from the GenBank database, or had incomplete or mismatched sequences. To improve identifications, we sequenced 31 specimens representing 18 species from scientific collections at Monmouth University, and from bait stores and fish markets. This work was largely done by student researcher and co-author Lyubov Soboleva, a senior at John Bowne High School in New York City. We deposited these new sequences in GenBank, boosting the database’s coverage to about 80 percent of our local species. </p>
<figure class="align-center zoomable">
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<figcaption>
<span class="caption">Study’s collection sites in Manhattan.</span>
<span class="attribution"><span class="source">Mark Stoeckle</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We focused on fish and other vertebrates. Other research groups have applied an aquatic eDNA approach to invertebrates. In principle, the technique could assess the diversity of all animal, plant and microbial life in a particular habitat. In addition to detecting aquatic animals, eDNA reflects terrestrial animals in nearby watersheds. In our study, the commonest wild animal detected in New York City waters was the brown rat, a common urban denizen.</p>
<p>Future studies might employ autonomous vehicles to routinely sample remote and deep sites, helping us to better understand and manage the diversity of ocean life.</p><img src="https://counter.theconversation.com/content/75957/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Stoeckle receives funding from Monmouth University-Rockefeller University Marine Science Policy Initiative (MURU). </span></em></p>Animals shed bits of DNA as they go about their lives. A new study of the Hudson River estuary tracked spring migration of ocean fish by collecting water samples and seeing whose DNA was present when.Mark Stoeckle, Senior Research Associate in the Program for the Human Environment, The Rockefeller UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/702802016-12-21T06:40:03Z2016-12-21T06:40:03ZThese six utopian cities of the future will help you re-imagine life on Earth<figure><img src="https://images.theconversation.com/files/149877/original/image-20161213-1629-10e5t55.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">Alan Marshall</span>, <span class="license">Author provided</span></span></figcaption></figure><p><a href="http://www.bl.uk/learning/histcitizen/21cc/utopia/utopia.html">Utopia</a>, a book by English statesman, lawyer and clergyman <a href="http://www.biography.com/people/thomas-more-9414278">Thomas More</a> (1487-1535), turns 500 years old this month.</p>
<p>A fictional rendering of social philosophy, the book describes an exemplary society on an imaginary island in an unknown place faraway across the seas. </p>
<p>Coined by More from the Greek <em>ou-topos</em>, meaning no place, or nowhere, the word <a href="http://www.encyclopedia.com/social-sciences-and-law/political-science-and-government/political-science-terms-and-concepts-94">utopia has become adopted in the English language</a> to mean a place where everything is ideal or perfect. </p>
<p>In celebrating Utopia’s 500th birthday, the <a href="http://www.ecotopia2121.com/">Ecotopia 2121 project</a>, of which I am the coordinator, is harnessing Thomas More’s spirit to predict the futures of 100 real cities around the world – if they somehow managed to become super eco-friendly. </p>
<p>Of course, modern utopias need to be eco-friendly to overcome the global environmental crisis. Given that cities may be home to <a href="https://shared.uoit.ca/shared/faculty-sites/sustainability-today/publications/population-predictions-of-the-101-largest-cities-in-the-21st-century.pdf">80% of humanity by the end of the century</a>, they can only be sustainable if environmentalism is one of their core features.</p>
<p>The cities of Ecotopia 2121 are presented in the form of “scenario art”, which involves a review of both global and local environmental challenges as well as their unique histories and cultures. This allows for a diversity of future scenarios rather than one common vision of the “future city”.</p>
<p>What you will see below are a series of artworks, but this is not an art project. We use art as a means of analysis and communication. </p>
<p>With that in mind, here are six ecotopian cities of my own creation that emerged from the project, one from each inhabited continent.</p>
<h2>Accra 2121</h2>
<p>Accra, the <a href="http://www.africa.com/insiders-guide-to-african-business-travel-accra-ghana/">capital of Ghana</a>, is exposed to disastrous floods every year. This has been made worse by climate change, as well as <a href="http://www.tandfonline.com/doi/abs/10.1080/19463138.2014.984720">unregulated construction and dumping in and around its waterways</a>. </p>
<p>In our imagined future, locals seek to procure housing above the floodline, by building low-cost tree cabins in the nearby forest. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149862/original/image-20161213-1615-is5a2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Accra 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Ghana has one of the <a href="http://www.ghanaweb.com/GhanaHomePage/NewsArchive/Ghana-has-the-Highest-Rate-of-Deforestation-212616">highest deforestation rates in the world</a>, but by 2121, the forest has become a home for some of its citizens. </p>
<p>Accra’s new residents would protect the forest ecosystem from those who would destroy it, such as the logging, mining and oil companies. </p>
<h2>London 2121</h2>
<p>In the summer of 2121, during an economic downturn, 100,000 pensioners take to the streets of <a href="http://www.visitlondon.com/">London, the British capital</a>, to protest cuts in pensions and education, shutting down the entire city. </p>
<p>They bring along their grandchildren to give them something interesting to do as they mind them. By summer’s end, the protesters despair at the government’s poor response, so they take matters into their own hands, staging a permanent occupation. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149853/original/image-20161213-1596-wf9uvd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">London 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The pensioners convert some 20km² of London into a large eco-village, transforming unoccupied offices into homes, sowing garden lots on street corners, and setting up eco-businesses to trade products and services. </p>
<p>In the process, all the children get free education from their experienced elders in these various green arts and crafts. </p>
<h2>Los Angeles 2121</h2>
<p>The <a href="http://www.discoverlosangeles.com/">southern Californian city of Los Angeles</a> once had a great network of tramways, but this was systematically bought up and then closed down by a group of <a href="https://www.theguardian.com/cities/2016/apr/25/story-cities-los-angeles-great-american-streetcar-scandal">conspiring auto-manufacturing companies</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149855/original/image-20161213-1625-vweko0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Los Angeles 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As the world’s oil is depleted by the end of this century, cars will become useless and trams could make a comeback in Los Angeles. The unused freeways could then be redeveloped into vegetated greenways. Such greenways are suited for pedestrians and cyclists, but they could also act as ecological corridors, connecting populations of wild plants and animals around the city that would otherwise be isolated. </p>
<p>Retired cars could then serve as part of the fabric of high-density buildings, creating an architectural style whereby people live and work in smaller structures and within tighter-knit communities. This would mean cities such as Los Angeles would not need to sprawl further into the countryside and wild lands.</p>
<h2>Rēkohu 2121</h2>
<p>Known in English as the Chatham Islands, <a href="http://www.moriori.co.nz/rekohu/">Rēkohu is an archipelago in the Pacific Ocean</a>, 680km southeast of New Zealand. It’s the ancestral home of the <a href="https://infogr.am/themoriori-genocide">pacifist Moriori people</a>, who came to wear the feathers of the native albatross in their hair to <a href="http://www.jstor.org/stable/20705461">symbolise peace</a> during the 500 years they lived on the archipelago.</p>
<p>In the 19th century, British sealers and Maori warriors from New Zealand discovered the islands. The sealers <a href="https://www.nzgeo.com/stories/moriori-a-pride-reborn/">decimated the colonies of the animals and introduced devastating diseases</a> to which the Moriori had no immunity. Then the Maori staged a <a href="http://www.teara.govt.nz/en/moriori">violent takeover of the islands</a>, slaughtering or enslaving the remaining Moriori. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149858/original/image-20161213-1594-bg90xp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rēkohu 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The Moriori refused to give up their pacifist ideals to fight against the invaders. While this history suggests pacifism is only going to get you killed or enslaved, the <a href="http://www.moriori.co.nz/">Moriori who survive today</a> believe otherwise. They maintain that their pacifism meant that they lived in a peaceful society for five centuries. </p>
<p>By 2121, their small capital city on the lagoon is home to a peace school that expounds the virtues of pacifism to the rest of the world.</p>
<h2>Salto del Guairá 2121</h2>
<p>The <a href="http://www.amusingplanet.com/2014/10/guaira-falls-natural-wonder-flooded-by.html">Guairá Falls</a> along the border of Paraguay and Brazil were once a natural wonder. The cacophonous roar of their seven columns could be heard many kilometres away and, for many years, the falls were a major attraction. They were also the economic lifeblood of the nearby Paraguayan city of <a href="http://www.saltodelguaira.gov.py/">Salto del Guairá</a>, which thrived on tourism. </p>
<p>In 1982, however, the <a href="https://www.internationalrivers.org/blogs/232/farewell-seven-falls">Brazilian military government blew away the rocks</a> over which the water fell, to create a reservoir for a dam. Many Paraguayans mourned the passing of their much-loved falls. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149859/original/image-20161213-1613-rdpdux.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Salto del Guairá 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>By 2121, though, both the falls and the city have re-emerged in splendid style. The dam has collapsed through neglect and local people have regained control of their land. They set about rehabilitating the falls as best they can, turning their home into a scenic eco-city that attracts tourists once again. </p>
<h2>Tokyo 2121</h2>
<p>After a nuclear meltdown just out of town, a vast radioactive cloud sweeps over future Tokyo. Everyone must be evacuated. A few hardy “nuclear families” tough it out in “moonbase” homes, which are impervious to radiation. </p>
<p>Everything these families eat and drink must be produced and recycled within these homes. When they step outside, they must don protective clothing or “moonsuits”. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=333&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=333&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=333&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=419&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=419&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149861/original/image-20161213-1596-pgo3t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=419&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Tokyo 2121.</span>
<span class="attribution"><span class="source">Alan Marshall</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But because Tokyo is suddenly depopulated, it’s not nearly as noisy and stressful as before. If <a href="http://www.the-philosophy.com/sartre-hell-is-other-people">“hell is other people”</a>, as French philosopher Jean-Paul Sartre suggested, then Tokyo 2121 is utopia. </p>
<p>Wildlife also rebounds, albeit in a mutated manner. </p>
<h2>Why Ecotopia 2121?</h2>
<p>These six scenarios are but a small sample of the 100 that were produced within <a href="http://www.ecotopia2121.com">the Ecotopia 2121 project</a>. Some readers will be delighted and others confused by the method of the project and its results. </p>
<p>Part of the <a href="http://utopian-studies.org/">point of utopianism</a> is to be provocative. If you like your future riddled with self-driving cars and the magic of nuclear energy, then maybe these scenarios are not for you. And you’re likely to dismiss them as fantasy anyway.</p>
<p>But to study utopias – and formulate alternative scenarios to how we now live on this planet – is not an escape into fantasy. It is an active response to the many technological fantasies cast about with extravagance and excess into our lives right now. </p>
<p>These fantasies bind us to an unsustainable and unlivable future. If Ecotopia 2121 is but a collection of fantasies, at least they would do less harm to the planet we live on.</p><img src="https://counter.theconversation.com/content/70280/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alan Marshall is the coordinator of the Ecotopia 2121 project.</span></em></p>Given that cities may be home to 80% of humanity by the end of the century, they can only be sustainable if eco-friendliness is one of their core features.Alan Marshall, Lecturer in Environmental Social Sciences, Faculty of Social Sciences and Humanities, Mahidol UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/695562016-12-16T00:40:39Z2016-12-16T00:40:39ZGetting smarter about city lights is good for us and nature too<p>Ideas to enhance the liveability and <a href="http://www.nespurban.edu.au">sustainability of our cities</a> have attracted a lot of interest recently. Examples include establishing or enhancing “<a href="http://melbourneurbanforestvisual.com.au/#issues">urban forests</a>”, or “<a href="https://luismataresearch.files.wordpress.com/2016/10/target-species-for-rewilding-monitoring-and-public-engagement-in-the-city-of-melbourne-mata-et-al-2016-29june2016-v3.pdf">bringing back nature</a>” into cities to support animals and ecosystems displaced by human activity. </p>
<p>While these projects focus on creating space for nature and enhancing biodiversity within cities, they rarely consider the impact on nature of the artificial lighting used across the urban landscape.</p>
<p>Public lighting is often thought to be essential for improving safety and preventing crime. Most commercial and public structures are lit up at night, although often for purely aesthetic reasons. </p>
<p>A network of street lighting links these “islands of illumination”. The effects of this can, in some large cities, result in “sky glow” that interferes with star visibility at distances of more than <a href="http://www.sciencedirect.com/science/article/pii/S0921800909004121">300 kilometres</a>.</p>
<h2>A cascade of harmful impacts</h2>
<p>While modern life makes some artificial lighting essential, when it’s overused or poorly designed it creates light pollution. It is not widely appreciated that this can have significant adverse effects, which go beyond interference with stargazing. These include serious impacts on humans, <a href="https://islandpress.org/book/ecological-consequences-of-artificial-night-lighting">plants and animals</a>.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2627884/">Effects on humans</a> reportedly include (but are not limited to) an increased risk of breast cancer, sleep disruptions and possible links to metabolic disorders, including diabetes and obesity. Furthermore, artificial lighting uses <a href="https://www.theclimategroup.org/project/led-scale">large amounts of energy</a> associated with CO<sub>2</sub> emissions.</p>
<p>Adverse effects on animals include interference with reproduction, <a href="https://theconversation.com/bright-city-lights-are-keeping-ocean-predators-awake-and-hungry-68965">predator and prey interactions</a>, and <a href="http://onlinelibrary.wiley.com/doi/10.1890/1540-9295(2004)002%5B0191:ELP%5D2.0.CO;2/full">orientation and migration</a>. These effects are potentially damaging for entire ecosystems, as well as particular species. </p>
<p>Ecosystems involve a complex balance of interactions between species. Disrupting this can trigger a cascade of harmful effects.</p>
<p>The <a href="http://www.sciencedirect.com/science/article/pii/S000632071100231X">attraction of moths to lights</a> offers an illustration of this. In becoming disoriented and infinitely attracted to the artificial light, the local moths of a given species become an easy meal for bats and other predators, and the moth population declines. Other species that depend on the moths for their survival are now themselves at risk. </p>
<p>If this particular species of moth pollinates plants, then local <a href="https://theconversation.com/fatal-attraction-how-street-lights-prevent-moths-from-pollinating-60331">pollination may be reduced</a>. And if this moth is the only pollinator of a plant species, then that species’ rate of reproduction will fall. This can be devastating for insect and animal communities that rely on these plants for habitat and food. </p>
<p>A whole ecosystem can be harmed by something as apparently harmless as public lighting.</p>
<h2>A need to rethink lighting standards</h2>
<p><a href="http://onlinelibrary.wiley.com/doi/10.1890/1540-9295(2004)002%5B0191:ELP%5D2.0.CO;2/full">Despite awareness of adverse effects</a>, the collective ecological impact of artificial light is not well recognised beyond the sphere of ecological research.</p>
<p>Planning regulations and practices tend not to consider artificial lighting as a source of pollution. Rather, the focus is on minimum lighting standards, reflecting perceptions of safety and community expectations. </p>
<p>Questions of unwanted light are more often considered in terms of nuisance or energy wastage. The focus of light reduction tends to be on cost savings, or even CO<sub>2</sub> savings, and not wider environmental effects. Ironically, the introduction of energy-saving lighting, such as LED, may lead to <a href="http://phys.org/news/2016-03-energy-efficient-unexpected-ecological.html">even greater impacts on some species</a>. </p>
<p>Being diurnal creatures, we humans tend to have little awareness of night-time ecosystems. Given that light emissions disappear once the source is turned off, it is unsurprising that artificial light has not been identified as an important pollutant.</p>
<p>Global concerns about climate change and energy consumption, and the resulting trend towards greater efficiency and sustainability, create an opportunity to challenge the underlying assumptions about public lighting. For example, the notion that more lighting equates to greater safety and discourages crime <a href="http://cs.astronomy.com/asy/b/astronomy/archive/2015/07/29/humans-cling-to-their-primal-fear-of-the-dark.aspx">may be questionable</a>.</p>
<p>Reconsidering our association of artificial lighting with progress and modernity allows us to reframe the “minimum lighting standards” model to one that seeks to minimise harm in all respects. The key question then is what lighting is needed for human safety while <a href="http://www.sciencedirect.com/science/article/pii/S0264837711001165">minimising unwanted or harmful light as well as energy consumption?</a></p>
<p>Possible solutions go <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2012.02212.x/full">beyond a debate of more versus less lighting</a>. We could, for instance, use lights with <a href="http://www.sciencedirect.com/science/article/pii/S000632071100231X">wavelengths that cause less disruption to key species</a>, as well as “<a href="https://en.wikipedia.org/wiki/Intelligent_street_lighting">adaptive street lighting</a>” that responds to pedestrian movement. There are doubtless many possible innovations that balance human and ecological needs.</p>
<p>Urban greening programs could play a leading role here in developing smarter lighting solutions that benefit both humans and ecosystems. Such initiatives would be natural inclusions in the emerging protocols to guide <a href="https://ggarrardresearch.files.wordpress.com/2012/11/bsud-final_reduced-size2.pdf">biodiversity-sensitive urban design</a>.</p><img src="https://counter.theconversation.com/content/69556/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alex Kusmanoff receives funding from the Australian Research Council and through the National Environment Science Programme's Threatened Species and Clean Air and Urban Landscapes Hubs.</span></em></p><p class="fine-print"><em><span>Georgia Garrard receives funding from the National Environmental Science Programme's Threatened Species Recovery Hub.</span></em></p><p class="fine-print"><em><span>Luis Mata receives funding from the National Environmental Science Programme - Clean Air and Urban Landscapes Hub.</span></em></p><p class="fine-print"><em><span>Sarah Bekessy receives funding from the Australian Research Council and through the National Environment Science Programme's, Threatened Species and Clean Air and Urban Landscapes Hubs.</span></em></p>Urban greening programs need to consider the harmful impacts of artificial lighting on ecosystems. Fortunately, we can do a lot to create more biosensitive lighting.Alex Kusmanoff, PhD candidate, Inter-disciplinary Conservation Science and Research Group, RMIT UniversityGeorgia Garrard, Research fellow, Interdisciplinary Conservation Science Research Group, RMIT UniversityLuis Mata, Postdoctoral research fellow, RMIT UniversitySarah Bekessy, Associate professor, RMIT UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/699572016-12-09T16:24:50Z2016-12-09T16:24:50ZPlanet Earth II: why most animals can’t hack city living<figure><img src="https://images.theconversation.com/files/149450/original/image-20161209-31352-1fxy53t.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">BBC NHU/Fredi Devas</span></span></figcaption></figure><p>The grand finale of the BBC’s Planet Earth II showcased the ingenious strategies that some animals use to thrive in urban environments. Though impressive, these species are in the minority. As the number of people living in cities around the world continues to rise, we should really be turning our attention to those animals that find city living too hard to handle.</p>
<p>Urbanisation represents the most extreme form of habitat loss for most plants and animals. As towns and cities grow, human beings live together in higher densities, and natural habitat is removed and replaced with hard, impermeable structures such as roads and buildings. Harmful pollution increases, as does the noise from industry and traffic, the amount of artificial lighting and the number of introduced predators such as cats. </p>
<p>As remaining pockets of natural or semi-natural habitat (such as remnant native habitat or man-made parks) become more isolated, city-dwelling animals are prevented from venturing out to look for food, resting places or mates, or may risk dying in the attempt. All together, these changes make cities impossible places for many species to live in. </p>
<h2>Life in the urban jungle</h2>
<p>Typically, we find a lower variety of plants and animals in more built-up areas; and this applies to all groups of wildlife. In <a href="http://rspb.royalsocietypublishing.org/content/281/1780/20133330.short">a recent global study</a>, researchers estimated that cities accommodate only 8% of the bird species and 25% of the plants that would have lived in those areas prior to urban development. As a <a href="http://www.bbc.co.uk/schools/gcsebitesize/science/ocr_gateway_pre_2011/environment/0_ecology_organisms4.shtml">vertebrate’s</a> territory becomes more urban, it’s also more likely to be <a href="http://www.iucnredlist.org/">threatened with extinction</a>. In fact, <a href="http://www.sciencedirect.com/science/article/pii/S0006320708001432">it’s estimated that</a> urban development is responsible for the listing of 420 vertebrate species around the planet as threatened. </p>
<p>It’s the generalist, opportunistic species such as foxes and rats – and, as we see on the programme, some monkeys – which can adapt to a wide variety of environmental conditions. By contrast, creatures that require large areas to source enough food, have specialist habitats or dietary requirements, or those with narrow geographic ranges tend to fare poorly during urban development. </p>
<p>In 2011, the <a href="http://www.biologicaldiversity.org">Center for Biological Diversity</a> released a list of ten US species facing extinction as a result of human population growth. Several of these have been directly affected by urban development; including the Florida panther and the Mississippi gopher frog, and the Lange’s metalmark butterfly. There are only 150 of these butterflies left in the world, living in a small coastal refuge in California which, incidentally, is also home to the last natural populations of a number of wildflower species including the Antioch Dunes evening primrose and Contra Costa wallflower.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149455/original/image-20161209-31405-4hr05p.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">Bat nap.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/124758008@N06/14659611027/sizes/l">FBG_Paris/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Bats are another group of animals that frequently lose out from urbanisation. This is partly because many species are reliant on forests for their food and roosting spots. Yet even bats which we often see in cities can find it difficult to cope with the most built-up areas. </p>
<p>For example, the common pipistrelle is widespread throughout Europe – it can often be spotted roosting in buildings and flying around urban parks. But <a href="http://www.sciencedirect.com/science/article/pii/S0006320714004479">research at the University of Stirling</a>, using citizen science as part of the Bat Conservation Trust’s National Bat Monitoring Programme, found that this bat was far less likely to be recorded in densely built-up areas, compared to less built-up ones. </p>
<h2>Growing greener cities</h2>
<p>About half the world’s human population currently live in urban areas, which cover about 3% of the earth’s land surface. Both of these figures <a href="http://www.earthinstitute.columbia.edu/news/2005/story03-07-05.html">are increasing rapidly</a>. At the same time, urban areas are likely to spread fastest in some of the most biologically diverse areas of the world, including parts of Africa and Asia, which will place <a href="http://www.pnas.org/content/109/40/16083">even more species at risk</a>. For example, one of the areas predicted to undergo the fastest levels of urban development is Africa’s Eastern Afromontane, home to an astonishing array of plants and animals that do not exist anywhere else. Several species of giraffe, which were <a href="http://www.bbc.co.uk/news/science-environment-38240760">recently listed as threatened</a>, are also found in this area. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/149452/original/image-20161209-31370-h40suz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Strategic greenery: Singapore’s solar trees.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/babomike/7911423326/sizes/l">BaboMike/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>Losing a species to extinction is not just a tragedy for the animal kingdom. Humans rely on biological diversity for a huge array of “services”, which they provide us with; whether directly for food or timber, or indirectly, through nutrient cycling, pollination and the provision of clean water and air. </p>
<p>Yet the situation is not entirely hopeless. There are many courses of action we can take, as individuals on a local level, and as a society by developing sustainable strategies for urban planning. Many studies show that maintaining and expanding green spaces in cities (including gardens) assists with wildlife conservation and enhances human health and well-being. And green roofs and walls can provide habitats for wildlife and reduce the impact of the <a href="https://theconversation.com/explainer-why-are-cities-warmer-than-the-countryside-53160">urban heat island</a>, as well as absorbing rainwater and improving building insulation. </p>
<p>While it’s incredible to see hyenas living in harmony with humans, falcons soaring between skyscrapers and monkeys leaping through the urban jungle, we must also spare a thought for those species which can’t handle city living. As urban environments continue to expand and develop around the world, it’s worth remembering this: if we can make cities more habitable for wildlife, then we humans will benefit too.</p><img src="https://counter.theconversation.com/content/69957/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kirsty Park is a Trustee of the Bat Conservation Trust. </span></em></p>Some animals love living in the urban jungle – but they are a small minority, compared to those we risk losing to urbanisation.Kirsty Park, Professor in Conservation Ecology, University of StirlingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/655662016-10-03T19:15:36Z2016-10-03T19:15:36ZWhy ‘green cities’ need to become a deeply lived experience<figure><img src="https://images.theconversation.com/files/139509/original/image-20160928-30432-maf2s1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Greening Manhattan: bringing nature into the city is one thing, making it part of our culture and everyday lives is another.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/alykat/5850122/in/photolist-vZ3b-a3QzkX-5ikuT5-4NkyDh-bzkgv7-bzkero-4NgmnB-bzkgvj-4NkyLs-4NgmpP-6yqjY7-bzkgvA-3Z4w1-8RZir4-oZGoMF-zq28Kj-GGhuyy-6Ft3Hy-etppFv-8acTUd-o32TGV-Fg76jP-aFNnFc-9jeTPT-dSfE9t-eMQx2P-9LSQJy-gpaNg4-45QSRn-6mkDJB-tmzt5-xqHWwT-9DHr65-efsqqt-8qrzr7-a2Dc8n-mSg1oR-fo5nKe-ynZUEK-fT9v2r-zb48SV-uD8Q43-7Z5YMY-tyFie3-7wBccE-es9LBm-dtyty5-JNxysL-8hBdNt-2i6ct">Alyson Hurt/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p><em>Australian cities are inherently diverse places, but that diversity can lead to conflict between different values about what cities should and can be. Our series, <a href="https://theconversation.com/au/topics/conflict-in-the-city-31714">Conflict in the City</a>, brings together urban researchers to examine some of these tensions and consider how cities are governed and for whom.</em></p>
<hr>
<p>Enthusiasm for urban greening is at a high point, and rightly so.</p>
<p>Ecological studies highlight the contribution urban nature makes to the conservation of biodiversity. For example, research shows cities support a <a href="http://onlinelibrary.wiley.com/doi/10.1111/geb.12404/abstract">greater proportion of threatened species</a> than non-urban areas. </p>
<p>Green space is increasingly recognised as useful for moderating the <a href="https://theconversation.com/explainer-why-are-cities-warmer-than-the-countryside-53160">heat island effect</a>. Hence, this helps cities adapt to, and reduce the consequences of, climate change. </p>
<p>Reducing urban heat stress is the main objective behind the <a href="http://www.smh.com.au/federal-politics/political-news/turnbull-governments-plan-to-make-cities-cooler-and-greener-20160118-gm8fdz.html">federal government’s plan</a> to set tree <a href="https://theconversation.com/concrete-jungle-well-have-to-do-more-than-plant-trees-to-bring-wildlife-back-to-our-cities-51047">canopy targets for Australian cities</a>. Trees are cooler than concrete. Trees <a href="https://theconversation.com/in-a-heatwave-the-leafy-suburbs-are-even-more-advantaged-53307">take the sting out of heatwaves</a> and <a href="https://theconversation.com/building-cool-cities-for-a-hot-future-57489">reduce heat-related deaths</a>.</p>
<p>The “healthy parks healthy people” agenda emphasises the health benefits of trees, parks and gardens. Urban greenery provides a pleasant place for recreation. By enhancing liveability, green spaces make cities more desirable places to live and work.</p>
<p>The increased interest in urban greening presents exciting opportunities for urban communities long starved of green space.</p>
<h2>Unpacking the green city agenda</h2>
<p>This enthusiasm for “green cities” stands in stark contrast to traditional views about nature as the antithesis of culture, and so having no place in the city. The traditional view was that the only ecosystems worthy of protection were to be found beyond the city, in national parks and wilderness areas.</p>
<p>We embrace the new agenda wholeheartedly, but also believe it’s important not to focus solely on instrumental measures like canopy cover targets to reduce heat stress. We should not forget about experiential encounters.</p>
<p>The risk with instrumental (and arguably exclusionary) approaches is these fail to challenge the divide between people and nature. This limits people’s connection to the places in which they live and to broader ecological processes that are essential for life. </p>
<p>Instrumental targets in isolation also risk presenting urban greening as an “apolitical” endeavour. But we know this is not the case, as we see with the rise of <a href="http://plt.sagepub.com/content/early/2016/06/28/1473095216654448.refs">green gentrification</a> associated with iconic greening projects like <a href="http://www.thehighline.org/about">New York’s High Line</a>. Wealthy suburbs consistently have the most green space in cities.</p>
<p><a href="https://theconversation.com/concrete-jungle-cities-adapt-to-growing-ranks-of-coyotes-cougars-and-other-urban-wildlife-43588">Bringing nature into the city</a> is one thing. Bringing it into our culture and everyday lives is another.</p>
<h2>Understanding ecology in a lived sense</h2>
<p>Urban greening provides an opportunity to recast the relationship between people and environment – one of the critical challenges associated with <a href="https://theconversation.com/an-official-welcome-to-the-anthropocene-epoch-but-who-gets-to-decide-its-here-57113">the Anthropocene</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=903&fit=crop&dpr=1 600w, https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=903&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=903&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1135&fit=crop&dpr=1 754w, https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1135&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/139517/original/image-20160928-30448-36gd6a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1135&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Urban greening is not just for our benefit, but must surely be for our co-habitants too.</span>
<span class="attribution"><span class="source">Matt Cornock/flickr</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>To break down nature-culture divides in our cities, and in ourselves, we argue for the importance of embracing experiential engagements that develop a more deeply felt connection with the city places in which we live, work and play. </p>
<p>We are advocating a focus that does more than just encourage people to interact tangibly in and with urban nature, by drawing attention to the way humans and non-humans (including plants) are active co-habitants of cities.</p>
<p>Such an approach works by recognising that human understanding of the environment is intricately <a href="https://books.google.com.au/books?id=wwzUj2o42fUC">wrapped up in our experiences of that environment</a>. </p>
<p>Put simply, green cities can’t just be about area, tree cover and proximity (though they are important). We need to <a href="http://link.springer.com/article/10.1007/s11625-016-0367-3">foster intimate, active and ongoing encounters</a> that position people “in” ecologies. And we need to understand that those ecologies exist beyond the hard boundaries of urban green space. </p>
<p>Without fostering a more holistic relationship with non-humans in cities, we risk an urban greening agenda that misses the chance to unravel some of the nature-culture separation that contributes to our long-term sustainability challenges as a society.</p>
<p>Active interactions with nature in the spaces of everyday life are vital for advancing a form of environmental stewardship that will persist beyond individual (and sometimes short-lived) policy settings.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=448&fit=crop&dpr=1 600w, https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=448&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=448&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=563&fit=crop&dpr=1 754w, https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=563&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/139514/original/image-20160928-30456-1sf5o04.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=563&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Green city citizens need to see themselves as part of, not separate from, the ecologies that exist beyond the hard boundaries of urban green space.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/8113246@N02/5160185705/in/photolist-8RZir4-oZGoMF-zq28Kj-GGhuyy-6Ft3Hy-etppFv-8acTUd-o32TGV-Fg76jP-aFNnFc-9jeTPT-dSfE9t-eMQx2P-9LSQJy-gpaNg4-45QSRn-6mkDJB-tmzt5-xqHWwT-9DHr65-efsqqt-8qrzr7-a2Dc8n-mSg1oR-fo5nKe-ynZUEK-fT9v2r-zb48SV-uD8Q43-7Z5YMY-tyFie3-7wBccE-es9LBm-dtyty5-JNxysL-8hBdNt-2i6ct-87eRGN-9W8ePg-5wMpDV-5L7riW-7Pa78m-5fL19N-88DCj7-btHvr3-nS9ies-7xnbpA-fgMjKA-9X1hfK-5ydqiH">PINKE/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<h2>No getting away from the politics</h2>
<p>It is important to consider the <a href="https://theconversation.com/if-planners-understand-its-cool-to-green-cities-whats-stopping-them-55753">policy and governance dimensions of urban greening</a>. </p>
<p>If the instrumental orientation prevails, our cities might be “more liveable” (at least for some, at particular locations and points in time), but our societies may not be more socially and environmentally just, or more sustainable.</p>
<p>We therefore emphasise the need to understand and critique the dimensions of the renewed interest in urban ecology. We have to consider whether this interest is associated with existing political economies, which embrace technocratic expertise to the exclusion of other voices, or whether urban greening can foster the emergence of a more transformative form of decision-making. </p>
<p>We also ask how we can enhance the prospects for more deliberative and place-based responses. An experiential turn for urban greening may be one way to make green space planning and practice more democratic. </p>
<p>By questioning who we might be greening for and how, we can open the way for the <a href="http://theconversation.com/how-can-we-meaningfully-recognise-cities-as-indigenous-places-65561">much-needed acknowledgment</a> of Indigenous histories and participation in the making of urban space.</p>
<p>Giving urban greening an experiential focus might also help open our eyes to the needs of the more-than-human. Rather than simply cultivating green spaces for a narrow set of anthropocentric benefits, we pose the question: who are the participants in urban greening? It’s a way of acknowledging that we inhabit cities with plants and other non-human lifeforms. </p>
<p>An interesting area of policy development that may be productive for urban greening is the idea of the <a href="http://www.playfulcommons.org/about/">playful commons</a>. This is an example of a governance approach that is more open to affective and experiential interaction – the community participates in negotiating, licensing and designing the use of public space. </p>
<p>Applying this approach to urban greening might encourage more deliberative forms of governance that can deliver more environmentally just and sustainable cities for the long term, for both humans and non-humans. </p>
<hr>
<p><em>You can read other Conflict in the City articles <a href="https://theconversation.com/au/topics/conflict-in-the-city-31714">here</a>.</em></p><img src="https://counter.theconversation.com/content/65566/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>The rise of urban greening is an opportunity to recast the relationship between people and environment. Humans and non-human species are ecologically intertwined as inhabitants of cities.Benjamin Cooke, Lecturer, School of Global, Urban and Social Studies, RMIT UniversityBrian Coffey, Lecturer, School of Global, Urban and Social Studies, RMIT UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/624152016-09-12T01:41:42Z2016-09-12T01:41:42ZScientist at work: Revealing the secret lives of urban rats<figure><img src="https://images.theconversation.com/files/136938/original/image-20160907-25257-1bcwvbu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Public park in Manhattan, home to a rat population with over 100 visible burrows</span> <span class="attribution"><span class="source">Dr. Michael H. Parsons</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In an era when we can decode language among animals and design coatings that make military weapons virtually invisible, it may seem that there are few things science cannot accomplish. At the same time, we are surprisingly ignorant about some things that are much more ordinary. For me, perhaps the most intriguing example is city rats, which in many ways are the most important species of urban wildlife in our increasingly urbanized world. </p>
<p>Because rats are small, vigilant and live mainly underground, even behavioral ecologists like me know remarkably little about how they move through cities and interact with their environments. That’s a problem because rats foul our foods, spread disease and damage infrastructure. As more people around the world move to densely packed cities, they become increasingly vulnerable to rat behaviors and diseases. That makes it critically important to understand more about rats and the pathogens they carry. </p>
<p>I decided to study urban rats to help fill some gaps in our knowledge of how they use their sense of smell to seek favored resources (food and potential mates), and how this attraction influences their fine-scale movements across particular types of corridors. </p>
<h2>Small animals with big impacts</h2>
<p>Rats like to feed on small quantities of human rubbish while remaining just out of sight, so they have been associated with humans since the rise of agriculture. The ancestors of today’s urban rats followed humans across the great migratory routes, eventually making their way by foot or ship to every continent. </p>
<p>In cities, rats can enter buildings through openings as small as a quarter. They also may “vertically migrate” upward and enter residential dwellings <a href="https://www.youtube.com/watch?v=0t2VPBF6Kp4">through toilets</a>. Because rats often make their way into homes from parks, subways and sewers, they can transport microorganisms they pick up from decomposition of wastes, thus earning the colloquial nickname of “disease sponges.” </p>
<p>Unlike humans, rats are not limited by the density of their population. In population biology, they are referred to as an <a href="https://www.britannica.com/science/r-selected-species">“r-adapted species,”</a> which means they mature rapidly, have short gestation periods and produce many offspring. Their typical life span is just six months to two years, but a female rat can produce up to 84 pups per year, and pups reach sexual maturity as soon as five weeks after birth. </p>
<p>Like other rodents (derived from the Latin word “rodere,” to gnaw), rats have large, durable front teeth. Their incisors rank at 5.5 on the Mohs scale, which geologists use to measure minerals’ hardness; for comparison, iron scores around 5.0. Rats use their constantly growing incisors to gain access to food. They can cause structural damage in buildings by chewing through wood and insulation, and trigger fires by gnawing on wiring. In garages, rats often <a href="http://www.popularmechanics.com/cars/how-to/a9998/what-happens-when-a-rat-decides-to-live-in-your-car-16393667/">nest inside cars</a>, where they will also chew through insulation, wires and hoses.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/136789/original/image-20160906-25260-l0joa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<span class="attribution"><a class="source" href="http://www.nature.nps.gov/geology/education/concepts/minerals.cfm">National Park Service</a></span>
</figcaption>
</figure>
<p>In addition to causing physical damage, rats spread diseases directly by passing infectious agents through their blood, saliva or wastes, and indirectly by serving as hosts for disease-carrying arthropods such as fleas and ticks. They are known vectors for Lyme disease, Rocky Mountain spotted fever, Toxoplasma, Bartonella, <a href="http://allafrica.com/stories/201608220314.html">Leptospira</a> and other microorganisms, many as yet unnamed. A seminal 2014 study <a href="http://mbio.asm.org/content/5/5/e01933-14.short">found 18 novel viruses</a> in 133 rats collected in Manhattan. </p>
<h2>Studying rats in the city</h2>
<p>Although they are abundant, wild rats are exceptionally difficult to study. They are small, live mainly underground and are active at night, out of most humans’ sight. When people do see rats they are most likely to notice either the sickest or the boldest individuals – such as the <a href="https://www.youtube.com/watch?v=UPXUG8q4jKU">“pizza rat”</a> captured in a 2015 viral video – and make inaccurate generalizations about all rats.</p>
<p>Scientists study animal behavior by analyzing many individuals so that we can detect variations and patterns in behaviors within a population. It may be funny to see a rat drag a whole slice of pizza down subway stairs, but it is much more interesting and useful to know that 90 percent of a population is drawn to foods that are high in fat and protein. To draw conclusions like this, we need to observe how many individual animals behave over time. </p>
<p>Biologists typically track wild animals and observe their movements by capturing them and fitting them with radio or GPS transmitters. But these methods are nearly useless in urban areas: radio waves cannot pass through rebar-reinforced concrete, and skyscrapers block satellite link-ups. </p>
<p>In addition to physical barriers, working with wild rats also poses social challenges. Rats are the pariahs of the animal world: We associate them with filth, disease and poverty. Rather than striving to learn more about them, most people want only to avoid them. That instinct is so strong that last December an Air India pilot flying a Boeing 787 Dreamliner from Mumbai to London made an <a href="http://www.dailymail.co.uk/travel/travel_news/article-3379095/Rats-plane-Packed-passenger-jet-bound-London-forced-make-mid-air-diversion-rodent-spotted-cabin.html">emergency landing</a> after a single rat was spotted on the plane.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/136961/original/image-20160907-16611-1mml7rf.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">Assessing the health of a rat prior to implanting a microchip.</span>
<span class="attribution"><span class="source">Dr. Michael H. Parsons</span></span>
</figcaption>
</figure>
<p>Working with Michael A. Deutsch, a medical entomologist at <a href="http://www.arrowexterminating.com/">Arrow Pest Control</a>, I have started designing studies to investigate urban rat behavior in situ so that we can, for the first time, learn the histories of individual animals in the wild. We capture rats by luring them with pheromones – natural scents that they find irresistible – and implant radio-frequency identification (RFID) microchips under their skin to identify each animal. This is the same technology that retail stores use to identify commercial products with bar codes and that pet owners can use to identify their dog or cat if it strays. </p>
<p>After we release the microchipped rats, we use scents to attract them back to specific areas and monitor when and how often they return. Using camera traps and a scale that the rats walk across, we can assess their health by tracking weight changes and looking for new wounds and bite marks. We also test their ability to penetrate barriers, such as wire mesh. And we repeatedly collect biological samples, including blood, stool and DNA, to document the rats’ potential to carry pathogens. We have become familiar enough with some rats to give them names that match their unique personalities.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/137276/original/image-20160909-13379-1n3oypr.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 newly microchipped rat, groggy but otherwise healthy.</span>
<span class="attribution"><span class="source">Dr. Michael H. Parsons</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In a <a href="http://journal.frontiersin.org/article/10.3389/fevo.2015.00146/full">pilot study</a> published last year, we reported some initial findings. By monitoring individual rats, we learned that males foraged around the clock 24 hours per day, but females did so only during late mornings. Females and males were equally attracted to scents from lab rats, and females responded to pheromones at the same rate as males. </p>
<p>In 2016 we <a href="http://dx.doi.org/10.3389/fpubh.2016.00132">published our detailed methods</a>
as a roadmap that other scientists can use to replicate this research. Using this approach, we believe scientists can learn when and where particular pathogens enter a given rat population. As far as we know, these are the first two studies to analyze wild city rats at the level of the individual in a major U.S. metropolitan area. </p>
<h2>Overcoming taboos against studying city rats</h2>
<p>In doing this research, I have encountered strong social taboos against working with rats. In 2013, while I was seeking opportunities to carry out field research on rats in New York City, I requested access to the CCTV surveillance cameras of <a href="http://forgotten-ny.com/1999/05/the-alleys-of-lower-manhattan-how-did-mill-lane-marketfield-strret-and-theatre-alley-get-their-names">“Theatre Alley,”</a> a narrow lane in Manhattan’s Financial District where rats scurried at will. Just a few weeks later, I learned that Theatre Alley had been hastily cleaned, changing the setting forever and removing information that could have provided useful insights into rat movements and behavior.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/137090/original/image-20160908-25257-ab48h6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The feeling isn’t mutual.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/denial_land/2911479223">caruba/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>We have also found that there is little money for this kind of research. Although New York City spends a lot of money training pest control workers and finding and exterminating rat colonies through public institutions such as the <a href="http://www.mta.info/">Metropolitan Transportation Authority</a> and the <a href="http://www1.nyc.gov/site/doh/index.page">Department of Health and Mental Hygiene</a>, there are few opportunities for academic studies. </p>
<p>Officials at public agencies think pragmatically and respond to a specific threat after a problem has been reported. Thus, it is understandable that they may be unreceptive to requests for access to subways for theoretical purposes, or for disease-related surveillance in the absence of a demonstrated threat that may or may not come to fruition. </p>
<p>Instead, Michael Deutsch and I are looking for New York City residents who will allow us to do scientific research in their homes, businesses, apartment buildings and other establishments, without fear of publicity, fines or judgment. To do this work on a larger scale, we need to do more work to build bridges between academic research and front-line public health and sanitation agencies.</p>
<p>In New York alone, up to six million people use the subway system every day, coming into close proximity with rats, and nearly one-fourth of more than 7,000 restaurants inspected so far this year have shown <a href="http://www.theepochtimes.com/n3/2141467-in-new-york-city-rats-and-humans-are-one-for-one-says-rat-expert/?utm_expvariant=D001_01&utm_expid=21082672-11.b4WAd2xRR0ybC6ydhoAj9w.1&utm_referrer=https%3A%2F%2Fnews.google.com%2F">signs of rat or mouse activity</a>. We clearly need to know more about urban rats: how they behave, where they travel, when and where they pick up diseases and how long they spread them, how these diseases affect rats’ health and, eventually, how rats transmit infections to humans.</p><img src="https://counter.theconversation.com/content/62415/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael H. Parsons does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Rats foul our food, spread disease and damage property, but we know very little about them. A biologist explains how he tracks wild rats in New York City, and what he’s learned about them so far.Michael H. Parsons, Scholar-in-Residence, Hofstra UniversityLicensed as Creative Commons – attribution, no derivatives.