'George' the Snail Marks First Documented Species Extinction of 2019

By Jason Bittel
On January 2, a snail named George shriveled up and died in his tank at the University of Hawaii. He was 14 years old, which for a land snail is pretty long in the tooth (or in George's case, radula). But in all of his years, George never sired any offspring. There were simply no mating partners to be found. In fact, George was the last known member of his species, Achatinella apexfulva. And the moment he slimed off this mortal coil, 2019 experienced its first documented extinction.
While George's death came as a bit of a surprise (it's tough to tell when a snail is ill), the extinction of his species has been a long time coming.
"Researchers and conservationists have been looking for this species [in the wild] for over 20 years and haven't had any luck with finding them," says wildlife biologist David Sischo, the coordinator of Hawaii's Snail Extinction Prevention Program.
Scientists actually thought A. apexfulva had already gone extinct back in the 1990s, until 10 of them were found in 1997 and brought under the university's care. The idea was to set up a captive population whose progeny researchers could one day release into the wild. Unfortunately, none of the baby snails hatched in the lab lasted very long—except George, who was named after the late "Lonesome George," the Pinta Island tortoise who was also the last of his kind.
While A. apexfulva has the distinction of being the first to die out this year, it is one of several hundred land snails to disappear from the Hawaiian Islands over recent decades. The archipelago was once home to about 750 land snail species—as many as you'd find in all of continental North America, says Sischo. Unfortunately, only around 10 percent remain, all of which are federally protected.
Such losses may not seem all that crucial at a time when species that are, shall we say, slightly more charismatic than your average mollusk—tigers, rhinos and North Atlantic right whales—are struggling to keep their dwindling populations viable. But the people of Hawaii feel differently.
The Hawaiian tree snail Partulina mighelsianaHawaii Department of Land and Natural Resources
In the Hawaiian culture, snails were thought to have voices and sing in the night, and the names of many native snails reflect this. For instance, Kani kua mauna translates to "music on the mountain ridges," and Kani kanahele means "voice of the forest." There's no scientific evidence to suggest that Hawaii's land snails can actually sing, and some experts believe that people were hearing crickets and misattributing the sounds to snails, which were much larger and easier to spot. Either way, the association stuck.
"Hawaiians didn't have a written language, and they passed on their genealogy through chant and through hula," said Sischo, referring to the traditional style of dance. "Snails personified that ability to pass on your genealogy, if you were a good chanter or singer. Even today, if someone called you a snail, it would be a compliment," he says. "It was a good omen to see or hear a snail."
But as it turns out, seeing a giant African land snail was a very bad omen for the islands' native ecosystems. Hawaiians began importing these oversize snails in 1936 because they looked cool in backyard gardens. The decorative giants, however, eventually escaped the garden and took to the wild, where they found a bounty of fruits and vegetables, including those in farmers' fields and orchards. By 1955, the invasive snails had caused so much damage that the state's agricultural sector decided to fight back by—wait for it—introducing another non-native snail.
Rosy wolfsnails hail from Florida, where they've earned a reputation for hunting down and gobbling up other snails and slugs. When other snails can't be found, rosy wolfsnails even eat each other, resulting in the nickname "cannibal snails."
The rosy wolfsnail hails from Florida, where it has earned a reputation for hunting down and eating other snails and slugs.Marcel Holyoak via Flickr
You see where this is going, don't you? Instead of focusing on Hawaii's invasive giant African land snails, the rosy wolfpacks mowed down all the native snails they could find. This massacre didn't play out just in Hawaii, by the way. A 2009 study found that of the 400 mollusk extinctions known to have occurred on oceanic islands, rosy wolfsnails were responsible for 134 of them. This is what happens when your wildlife management decisions mimic the logic of the song "I Know an Old Lady Who Swallowed a Fly."
To be fair, cannibal snails don't deserve all the blame. Rats, which came to Hawaii as stowaways on ships, also eat native snails, as do Jackson's chameleons, which came from Kenya through the pet trade. And the practice of threading snail shells onto certain ceremonial leis didn't help either. While this tradition itself probably didn't cause any extinctions, when mid-nineteenth-century Europeans began coveting snail-shell leis as souvenirs, things got out of hand. The demand led to people gathering up the gastropods in the hundreds of thousands. (FYI: It is now a federal offense to collect native snail shells.)
So, what will happen to Hawaii's ecology now that George and so many of his native cousins are gone? Sischo says it isn't clear. Because these volcanic islands more or less exploded out of the sea, they never had their own species of earthworms to break down plant matter—but they did have snails to take up the job of detritivore. As these species disappear, the process by which nutrients are processed and returned to the soil will be altered in ways we don't yet understand. The islands have other native snails, like A. apexfulva, that graze on the algae and fungi that accumulate on plants. Scientists have shown that trees with grazer snails tend to have less biofilm on them and support a greater diversity of fungi, algae and bacteria. Take the grazers away, says Sischo, and everything gets a lot more mundane, which could affect the plants' health.
Conservationists are still searching for more Georges in the wild, but the probability of finding one is very slim and gets slimmer every day. However, there may be hope for other snails on the ropes. Hawaii's Snail Extinction Prevention Program is currently holding in captivity 30 species from five islands. All 30 are either extinct in the wild or close to it, but unlike George, many of these survivors are getting it on.
"We are actively reintroducing four protected species now," says Sischo, "and we have quite a bit now that we'll be reintroducing back into the wild in the next few years. So it's not all bad news."
He says his organization is also "manning the lifeboat" by removing invasive species where they exist and adding predator-proof fencing to areas that are still relatively pristine.
Will future Hawaiians sing stories about saving the islands' snails one day? Only time will tell.
2018 left us with a mixed bag of hope and foreboding. With recent history in mind, what does 2019 have in store? He… https://t.co/oHxlJDDbgg— Rhea Suh (@Rhea Suh)1547648220.0
Jason Bittel writes the Species Watch column for onEarth.
Cities Can Help Migrating Birds on Their Way By Planting More Trees and Turning Lights Off at Night
By Frank La Sorte and Kyle Horton
Millions of birds travel between their breeding and wintering grounds during spring and autumn migration, creating one of the greatest spectacles of the natural world. These journeys often span incredible distances. For example, the Blackpoll warbler, which weighs less than half an ounce, may travel up to 1,500 miles between its nesting grounds in Canada and its wintering grounds in the Caribbean and South America.
Blackpoll warbler abundance in breeding, non-breeding and migration seasons. Cornell Lab of Ornithology / CC BY-ND
<p>For many species, these journeys take place at night, when skies typically are calmer and predators are less active. Scientists do not have a good understanding yet of how birds navigate effectively at night over long distances.</p><p><span></span>We study bird migration and how it is being affected by factors ranging from <a href="https://scholar.google.com/citations?user=S04C3UMAAAAJ&hl=en" target="_blank">climate change</a> to <a href="https://scholar.google.com/citations?user=pPk38-8AAAAJ&hl=en" target="_blank">artificial light at night</a>. In a recent study, we used millions of bird observations by citizen scientists to document the <a href="https://doi.org/10.1016/j.envpol.2020.116085" target="_blank">occurrence of migratory bird species in 333 U.S. cities</a> during the winter, spring, summer and autumn.</p>Blackpoll warbler. PJTurgeon / Wikipedia
<p>We used this information to determine how the number of migratory bird species varies based on each city's level of <a href="https://www.britannica.com/science/light-pollution" target="_blank" rel="noopener noreferrer">light pollution</a> – brightening of the night sky caused by artificial light sources, such as buildings and streetlights. We also explored how species numbers vary based on the quantity of tree canopy cover and impervious surface, such as concrete and asphalt, within each city. Our findings show that cities can help migrating birds by planting more trees and reducing light pollution, especially during spring and autumn migration.</p>Declining Bird Populations
<p>Urban areas contain numerous dangers for migratory birds. The biggest threat is the risk of <a href="https://doi.org/10.1650/CONDOR-13-090.1" target="_blank">colliding with buildings or communication towers</a>. Many migratory bird populations have <a href="http://dx.doi.org/10.1126/science.aaw1313" target="_blank">declined over the past 50 years</a>, and it is possible that light pollution from cities is contributing to these losses.</p><p>Scientists widely agree that light pollution can <a href="https://doi.org/10.1073/pnas.1708574114" target="_blank">severely disorient migratory birds</a> and make it hard for them to navigate. Studies have shown that birds will cluster around brightly lit structures, much like insects flying around a porch light at night. Cities are the <a href="https://doi.org/10.1002/fee.2029" target="_blank" rel="noopener noreferrer">primary source of light pollution for migratory birds</a>, and these species tend to be more abundant within cities <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.13792" target="_blank" rel="noopener noreferrer">during migration</a>, especially in <a href="https://doi.org/10.1016/j.landurbplan.2020.103892" target="_blank" rel="noopener noreferrer">city parks</a>.</p>Composite image of the continental U.S. at night from satellite photos. NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center
The Power of Citizen Science
<p>It's not easy to observe and document bird migration, especially for species that migrate at night. The main challenge is that many of these species are very small, which limits scientists' ability to use electronic tracking devices.</p><p>With the growth of the internet and other information technologies, new data resources are becoming available that are making it possible to overcome some of these challenges. <a href="https://doi.org/10.1038/d41586-018-07106-5" target="_blank">Citizen science initiatives</a> in which volunteers use online portals to enter their observations of the natural world have become an important resource for researchers.</p><p>One such initiative, <a href="https://ebird.org/home" target="_blank" rel="noopener noreferrer">eBird</a>, allows bird-watchers around the globe to share their observations from any location and time. This has produced one of the <a href="https://doi.org/10.1111/ecog.04632" target="_blank" rel="noopener noreferrer">largest ecological citizen-science databases in the world</a>. To date, eBird contains over 922 million bird observations compiled by over 617,000 participants.</p>Light Pollution Both Attracts and Repels Migratory Birds
<p>Migratory bird species have evolved to use certain migration routes and types of habitat, such as forests, grasslands or marshes. While humans may enjoy seeing migratory birds appear in urban areas, it's generally not good for bird populations. In addition to the many hazards that exist in urban areas, cities typically lack the food resources and cover that birds need during migration or when raising their young. As scientists, we're concerned when we see evidence that migratory birds are being drawn away from their traditional migration routes and natural habitats.</p><p>Through our analysis of eBird data, we found that cities contained the greatest numbers of migratory bird species during spring and autumn migration. Higher levels of light pollution were associated with more species during migration – evidence that light pollution attracts migratory birds to cities across the U.S. This is cause for concern, as it shows that the influence of light pollution on migratory behavior is strong enough to increase the number of species that would normally be found in urban areas.</p><p>In contrast, we found that higher levels of light pollution were associated with fewer migratory bird species during the summer and winter. This is likely due to the scarcity of suitable habitat in cities, such as large forest patches, in combination with the adverse affects of light pollution on bird behavior and health. In addition, during these seasons, migratory birds are active only during the day and their populations are largely stationary, creating few opportunities for light pollution to attract them to urban areas.</p>Trees and Pavement
<p>We found that tree canopy cover was associated with more migratory bird species during spring migration and the summer. Trees provide important habitat for migratory birds during migration and the breeding season, so the presence of trees can have a strong effect on the number of migratory bird species that occur in cities.</p><p>Finally, we found that higher levels of impervious surface were associated with more migratory bird species during the winter. This result is somewhat surprising. It could be a product of the <a href="https://www.epa.gov/heatislands" target="_blank">urban heat island effect</a> – the fact that structures and paved surfaces in cities absorb and reemit more of the sun's heat than natural surfaces. Replacing vegetation with buildings, roads and parking lots can therefore make cities significantly warmer than surrounding lands. This effect could reduce cold stress on birds and increase food resources, such as insect populations, during the winter.</p><p>Our research adds to our understanding of how conditions in cities can both help and hurt migratory bird populations. We hope that our findings will inform urban planning initiatives and strategies to reduce the harmful effects of cities on migratory birds through such measures as <a href="https://www.arborday.org/programs/treecityusa/index.cfm" target="_blank" rel="noopener noreferrer">planting more trees</a> and initiating <a href="https://aeroecolab.com/uslights" target="_blank" rel="noopener noreferrer">lights-out programs</a>. Efforts to make it easier for migratory birds to complete their incredible journeys will help maintain their populations into the future.</p><p><em><span style="background-color: initial;"><a href="https://theconversation.com/profiles/frank-la-sorte-1191494" target="_blank">Frank La Sorte</a> is a r</span>esearch associate at the </em><em>Cornell Lab of Ornithology, Cornell University. <a href="https://theconversation.com/profiles/kyle-horton-1191498" target="_blank">Kyle Horton</a> is an assistant professor of Fish, Wildlife, and Conservation Biology at the Colorado State University.</em></p><p><em></em><em>Disclosure statement: Frank La Sorte receives funding from The Wolf Creek Charitable Foundation and the National Science Foundation (DBI-1939187). K</em><em>yle Horton 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.</em></p><p><em>Reposted with permission from <a href="https://theconversation.com/cities-can-help-migrating-birds-on-their-way-by-planting-more-trees-and-turning-lights-off-at-night-152573" target="_blank">The Conversation</a>. </em></p>EcoWatch Daily Newsletter
By Lynne Peeples
Editor's note: This story is part of a nine-month investigation of drinking water contamination across the U.S. The series is supported by funding from the Park Foundation and Water Foundation. Read the launch story, "Thirsting for Solutions," here.
In late September 2020, officials in Wrangell, Alaska, warned residents who were elderly, pregnant or had health problems to avoid drinking the city's tap water — unless they could filter it on their own.
Unintended Consequences
<p>Chemists first discovered disinfection by-products in treated drinking water in the 1970s. The trihalomethanes they found, they determined, had resulted from the reaction of chlorine with natural organic matter. Since then, scientists have identified more than 700 additional disinfection by-products. "And those only represent a portion. We still don't know half of them," says Richardson, whose lab has identified hundreds of disinfection by-products. </p>What’s Regulated and What’s Not?
<p>The U.S. Environmental Protection Agency (EPA) currently regulates 11 disinfection by-products — including a handful of trihalomethanes (THM) and haloacetic acids (HAA). While these represent only a small fraction of all disinfection by-products, EPA aims to use their presence to indicate the presence of other disinfection by-products. "The general idea is if you control THMs and HAAs, you implicitly or by default control everything else as well," says Korshin.</p><p>EPA also requires drinking water facilities to use techniques to reduce the concentration of organic materials before applying disinfectants, and regulates the quantity of disinfectants that systems use. These rules ultimately can help control levels of disinfection by-products in drinking water.</p>Click the image for an interactive version of this chart on the Environmental Working Group website.
<p>Still, some scientists and advocates argue that current regulations do not go far enough to protect the public. Many question whether the government is regulating the right disinfection by-products, and if water systems are doing enough to reduce disinfection by-products. EPA is now seeking public input as it considers potential revisions to regulations, including the possibility of regulating additional by-products. The agency held a <a href="https://www.epa.gov/dwsixyearreview/potential-revisions-microbial-and-disinfection-byproducts-rules" target="_blank">two-day public meeting</a> in October 2020 and plans to hold additional public meetings throughout 2021.</p><p>When EPA set regulations on disinfection by-products between the 1970s and early 2000s, the agency, as well as the scientific community, was primarily focused on by-products of reactions between organics and chlorine — historically the most common drinking water disinfectant. But the science has become increasingly clear that these chlorinated chemicals represent a fraction of the by-product problem.</p><p>For example, bromide or iodide can get caught up in the reaction, too. This is common where seawater penetrates a drinking water source. By itself, bromide is innocuous, says Korshin. "But it is extremely [reactive] with organics," he says. "As bromide levels increase with normal treatment, then concentrations of brominated disinfection by-products will increase quite rapidly."</p><p><a href="https://pubmed.ncbi.nlm.nih.gov/15487777/" target="_blank">Emerging</a> <a href="https://pubs.acs.org/doi/10.1021/acs.est.7b05440" target="_blank" rel="noopener noreferrer">data</a> indicate that brominated and iodinated by-products are potentially more harmful than the regulated by-products.</p><p>Almost half of the U.S. population lives within 50 miles of either the Atlantic or Pacific coasts, where saltwater intrusion can be a problem for drinking water supplies. "In the U.S., the rule of thumb is the closer to the sea, the more bromide you have," says Korshin, noting there are also places where bromide naturally leaches out from the soil. Still, some coastal areas tend to be spared. For example, the city of Seattle's water comes from the mountains, never making contact with seawater and tending to pick up minimal organic matter.</p><p>Hazardous disinfection by-products can also be an issue with desalination for drinking water. "As <a href="https://ensia.com/features/can-saltwater-quench-our-growing-thirst/" target="_blank" rel="noopener noreferrer">desalination</a> practices become more economical, then the issue of controlling bromide becomes quite important," adds Korshin.</p>Other Hot Spots
<p>Coastal areas represent just one type of hot spot for disinfection by-products. Agricultural regions tend to send organic matter — such as fertilizer and animal waste — into waterways. Areas with warmer climates generally have higher levels of natural organic matter. And nearly any urban area can be prone to stormwater runoff or combined sewer overflows, which can contain rainwater as well as untreated human waste, industrial wastewater, hazardous materials and organic debris. These events are especially common along the East Coast, notes Sydney Evans, a science analyst with the nonprofit Environmental Working Group (EWG, a collaborator on <a href="https://ensia.com/ensia-collections/troubled-waters/" target="_blank">this reporting project</a>).</p><p>The only drinking water sources that might be altogether free of disinfection by-products, suggests Richardson, are private wells that are not treated with disinfectants. She used to drink water from her own well. "It was always cold, coming from great depth through clay and granite," she says. "It was fabulous."</p><p>Today, Richardson gets her water from a city system that uses chloramine.</p>Toxic Treadmill
<p>Most community water systems in the U.S. use chlorine for disinfection in their treatment plant. Because disinfectants are needed to prevent bacteria growth as the water travels to the homes at the ends of the distribution lines, sometimes a second round of disinfection is also added in the pipes.</p><p>Here, systems usually opt for either chlorine or chloramine. "Chloramination is more long-lasting and does not form as many disinfection by-products through the system," says Steve Via, director of federal relations at the American Water Works Association. "Some studies show that chloramination may be more protective against organisms that inhabit biofilms such as Legionella."</p>Alternative Approaches
<p>When he moved to the U.S. from Germany, Prasse says he immediately noticed the bad taste of the water. "You can taste the chlorine here. That's not the case in Germany," he says.</p><p>In his home country, water systems use chlorine — if at all — at lower concentrations and at the very end of treatment. In the Netherlands, <a href="https://dwes.copernicus.org/articles/2/1/2009/dwes-2-1-2009.pdf" target="_blank">chlorine isn't used at all</a> as the risks are considered to outweigh the benefits, says Prasse. He notes the challenge in making a convincing connection between exposure to low concentrations of disinfection by-products and health effects, such as cancer, that can occur decades later. In contrast, exposure to a pathogen can make someone sick very quickly.</p><p>But many countries in Europe have not waited for proof and have taken a precautionary approach to reduce potential risk. The emphasis there is on alternative approaches for primary disinfection such as ozone or <a href="https://www.pbs.org/wgbh/nova/article/eco-friendly-way-disinfect-water-using-light/" target="_blank" rel="noopener noreferrer">ultraviolet light</a>. Reverse osmosis is among the "high-end" options, used to remove organic and inorganics from the water. While expensive, says Prasse, the method of forcing water through a semipermeable membrane is growing in popularity for systems that want to reuse wastewater for drinking water purposes.</p><p>Remucal notes that some treatment technologies may be good at removing a particular type of contaminant while being ineffective at removing another. "We need to think about the whole soup when we think about treatment," she says. What's more, Remucal explains, the mixture of contaminants may impact the body differently than any one chemical on its own. </p><p>Richardson's preferred treatment method is filtering the water with granulated activated carbon, followed by a low dose of chlorine.</p><p>Granulated activated carbon is essentially the same stuff that's in a household filter. (EWG recommends that consumers use a <a href="https://www.ewg.org/tapwater/reviewed-disinfection-byproducts.php#:~:text=EWG%20recommends%20using%20a%20home,as%20trihalomethanes%20and%20haloacetic%20acids." target="_blank" rel="noopener noreferrer">countertop carbon filter</a> to reduce levels of disinfection by-products.) While such a filter "would remove disinfection by-products after they're formed, in the plant they remove precursors before they form by-products," explains Richardson. She coauthored a <a href="https://pubs.acs.org/doi/10.1021/acs.est.9b00023" target="_blank" rel="noopener noreferrer">2019 paper</a> that concluded the treatment method is effective in reducing a wide range of regulated and unregulated disinfection by-products.</p><br>Greater Cincinnati Water Works installed a granulated activated carbon system in 1992, and is still one of relatively few full-scale plants that uses the technology. Courtesy of Greater Cincinnati Water Works.
<p>Despite the technology and its benefits being known for decades, relatively few full-scale plants use granulated active carbon. They often cite its high cost, Richardson says. "They say that, but the city of Cincinnati [Ohio] has not gone bankrupt using it," she says. "So, I'm not buying that argument anymore."</p><p>Greater Cincinnati Water Works installed a granulated activated carbon system in 1992. On a video call in December, Jeff Swertfeger, the superintendent of Greater Cincinnati Water Works, poured grains of what looks like black sand out of a glass tube and into his hand. It was actually crushed coal that has been baked in a furnace. Under a microscope, each grain looks like a sponge, said Swertfeger. When water passes over the carbon grains, he explained, open tunnels and pores provide extensive surface area to absorb contaminants.</p><p>While the granulated activated carbon initially was installed to address chemical spills and other industrial contamination concerns in the Ohio River, Cincinnati's main drinking water source, Swertfeger notes that the substance has turned out to "remove a lot of other stuff, too," including <a href="https://ensia.com/features/drinking-water-contamination-pfas-health/" target="_blank" rel="noopener noreferrer">PFAS</a> and disinfection by-product precursors.</p><p>"We use about one-third the amount of chlorine as we did before. It smells and tastes a lot better," he says. "The use of granulated activated carbon has resulted in lower disinfection by-products across the board."</p><p>Richardson is optimistic about being able to reduce risks from disinfection by-products in the future. "If we're smart, we can still kill those pathogens and lower our chemical disinfection by-product exposure at the same time," she says.</p><p><em>Reposted with permission from </em><em><a href="https://ensia.com/features/drinking-water-disinfection-byproducts-pathogens/" target="_blank">Ensia</a>. </em><a href="https://www.ecowatch.com/r/entryeditor/2649953730#/" target="_self"></a></p>Trending
At a time of impending global food scarcity, cell-based meats and seafood have been heralded as the future of food.
- Most Meat Will Be Plant-Based or Lab-Grown in 20 Years, Analysts ... ›
- Lab-Grown Meat Debate Overlooks Cows' Range of Use Worldwide ... ›
- Will Plant-Based Meat Become the New Fast Food? - EcoWatch ›
One city in New Zealand knows what its priorities are.
Dunedin, the second largest city on New Zealand's South Island, has closed a popular road to protect a mother sea lion and her pup, The Guardian reported.
piyaset / iStock / Getty Images Plus
In an alarming new study, scientists found that climate change is already harming children's diets.
- No Country Is Protecting Children's Health, Major Study Finds ... ›
- 'Every Child Born Today Will Be Profoundly Affected by Climate ... ›