2021-05-31. [https://www.nytimes.com/interactive/2021/05/31/climate/wildlife-crossings-animals.html] – How Do Animals Safely Cross a Highway? Take a Look. Source: By Catrin Einhorn, The New York Times. Excerpt: The engineers were used to building overpasses for vehicles, not wildlife. But every spring and fall, collisions with mule deer and pronghorn spiked in the Pinedale region of Wyoming, where Route 191 disrupted the animals’ age-old migration paths. So the state Department of Transportation joined with the state wildlife agency and nonprofit groups to create a series of crossings, including the one pictured above. Collisions have dropped by roughly 90 percent. …Examples like that, along with earlier success stories from Canada and Europe, have led to a broad consensus on the value of animal crossings, according to environmentalists and transportation officials alike….
2021-03-25. After more than 2 decades of searching, scientists finger cause of mass eagle deaths. By Erik Stokstad, Science Magazine. Excerpt: More than 25 years ago, biologists in Arkansas began to report dozens of bald eagles paralyzed, convulsing, or dead. Their brains were pocked with lesions never seen before in eagles. The disease was soon found in other birds across the southeastern United States. Eventually, researchers linked the deaths to a new species of cyanobacteria growing on an invasive aquatic weed that is spreading across the country. …Today in Science, a team identifies a novel neurotoxin produced by the cyanobacteria and shows that it harms not just birds, but fish and invertebrates, too. …An unusual feature of the toxic molecule is the presence of bromine, which is scarce in lakes and rarely found in cyanobacteria. One possible explanation: the cyanobacteria produce the toxin from a bromide-containing herbicide that lake managers use to control the weed…. [https://www.sciencemag.org/news/2021/03/after-more-2-decades-searching-scientists-finger-cause-mass-eagle-deaths]
2021-01-12. Animal Planet. By Sonia Shah, Illustrations by Shyama Golden, The New York Times. Excerpt: An ambitious new system will track scores of species from space — shedding light, scientists hope, on the lingering mysteries of animal movement. …Last fall, teams of scientists began fanning out across the globe to stalk and capture thousands of other creatures — rhinos in South Africa, blackbirds in France, fruit bats in Zambia — in order to outfit them with an array of tracking devices that can run on solar energy and that weigh less than five grams. The data they collect will stream into an ambitious new project, two decades in the making and costing tens of millions of dollars, called the International Cooperation for Animal Research Using Space, or ICARUS, project. Each tag will collect data on its wearer’s position, physiology and microclimate, sending it to a receiver on the International Space Station, which will beam it back down to computers on the ground. This will allow scientists to track the collective movements of wild creatures roaming the planet in ways technically unimaginable until recently: continuously, over the course of their lifetimes and nearly anywhere on Earth they may go. By doing so, ICARUS could fundamentally reshape the way we understand the role of mobility on our changing planet. The scale and meaning of animal movements has been underestimated for decades…. [https://www.nytimes.com/interactive/2021/01/12/magazine/animal-tracking-icarus.html]
2020-10-03. A Toxic Alien Is Taking Over Russia. By Maria Antonova, The New York Times (Opinion). Excerpt: BALASHIKHA, Russia — …Russia is the biggest country on Earth and both the state and the people take pride in the size of its territory — “from the southern seas to the polar fringes,” as the current national anthem goes. That quiet emptiness, the enormousness of Russia, has been infiltrated in recent decades by an alien force: the giant hogweed. This invader, an exceptionally tall plant with a toxic sap that can cause third-degree burns and blindness, has come to symbolize the fate of rural Russia: malign neglect by the government. …In the summer, the giant hogweed assumes the look of dill on steroids; its coffee-table sized leaves create thickets impossible to pass without a hazmat suit. In the winter, it desiccates into a brown skeleton. Outside Moscow, the hogweeds are often the only visible landmarks over white fields, ominous umbrellas standing in the snow like War of the Worlds troops poised to march. Officials have begun to refer to overgrown areas as “contaminated.”… [https://www.nytimes.com/2020/10/03/opinion/sunday/russia-hogweed.html]
2020-03-18. Safe Passages. By Ben Guarino, Graphics by Joe Fox and Lauren Tierney, The Washington Post. Excerpt: Long-haul trucks roar along Interstate 80, a transportation backbone that stretches from San Francisco to just outside New York City. Traffic is so heavy here that the state’s transportation department recently counted a passing vehicle every 10 seconds, on average. This vital, four-lane corridor of commerce also threatens wildlife. It blocks the ancient north-south paths of mule deer, elk and pronghorn, creatures that embody the American West. …Wyoming officials and scientists have a plan: Build wildlife crossings to preserve migrations. Bridges, tunnels and other structures — imagine protected bike lanes, but for animals — can protect animals from hazards like highways and help them navigate a warming planet…. [https://www.washingtonpost.com/graphics/2020/climate-solutions/wyoming-wildlife-corridor/]
2019-12-05. Fractured Forests Are Endangering Wildlife, Scientists Find. By Carl Zimmer, The New York Times. Excerpt: The world’s forests are being carved into pieces. In tropical regions, animals are likely to pay a heavy price. …Around the world, humans are fracturing vast forests. Highways snake through the Amazon’s rain forests, and Indonesia plans an ambitious transportation grid in Borneo, through some of the largest untouched expanses of tropical forests. If you were to parachute at random into any of the planet’s forests, you’d probably land a mile or less from its edge, according to a recent study….
2019-11-05. We Have Broken Nature into More Than 990,000 Little Pieces. By Jenessa Duncombe, Eos/AGU. Excerpt: Habitat fragmentation is splintering undeveloped areas on Earth. … A new global survey has revealed that areas on Earth with little human impact are becoming smaller and more isolated. Human activity is continually bisecting forests and grasslands into smaller and smaller slivers of undeveloped land. Using satellite data, the new research suggests that 56% of the land on Earth—excluding areas covered in ice and snow—has relatively low human impacts. But that area is being parsed into ever-shrinking segments. Land with low human impact exists in roughly 990,000 fragments larger than 1 square kilometer, a much higher number than what occurs with natural boundaries of water, rock, and ice. The same area would be broken into just 73,000 fragments naturally…..
2019-10-11. Giant reptiles once ruled Australia. Their loss sparked an ecological disaster. By John Pickrell, Science Magazine. Excerpt: BRISBANE, AUSTRALIA—Saber-toothed cats, short-faced bears, and other ferocious mammals were the top predators of the ice age across most of the world. But not in Australia. Here, reptiles ruled: land-living crocs, monstrous snakes, and enormous relatives of the Komodo dragon, according to a study presented yesterday at the annual meeting of the Society of Vertebrate Paleontology here. The disappearance of these animals, the researchers argue, made room for mammalian predators to take over and set the stage for a massive extinction crisis that accelerated when Europeans arrived 200 years ago. “Between the expansion of agriculture in Australia, which changed the landscape, and the predators that we brought in, there was no way for native animals to escape,” says Kenny Travouillon, a paleontologist at the Western Australian Museum in Perth who was not involved in the study. …Most of these large reptiles, and the only large native mammal carnivores, had finally vanished by about 40,000 years ago along with Australia’s other megafauna, possibly because of changing climate. That left only small mammalian predators like the dog-size Tasmanian tiger and the even smaller Tasmanian devil to step into the role of apex predators across the continent. Price suggests these left ecosystems out of kilter. Things got worse about 4000 years ago when people introduced the dingo, a placental mammal from Asia that was a more efficient hunter than the Tasmanian tiger or devil and quickly outcompeted them. But it was the European introduction of the cat and the red fox in the past 200 years that has caused the most damage. These animals devastated small marsupials, which had evolved alongside the reptiles but were not used to dealing with more intelligent and effective placental mammal predators….
2019-07-11. Courting controversy, scientists team with industry to tackle one of the world’s most destructive crops. By Dyna Rochmyaningsih, Science Magazine. Excerpt: IN LIBO ON SUMATRA, INDONESIA—Crickets were chirping one clear morning in April when Anak Agung Aryawan walked under the canopy of a quarter-century-old oil palm plantation here. Suddenly Agung, an agroecologist, stopped. “Look, that’s a Sycanus!” He pointed at a black insect perched on a fern in the forest understory. Known as an assassin bug, Sycanus uses its mouthpart to stab its insect prey, including the fire caterpillar, one of the most important pests of oil palm trees. He soon found more insect killers in the palm grove: a Nephila spider, known for its big, elaborate web, and the bright yellow Cosmolestes, another species of assassin bug. Agung works for SMARTRI, an oil palm research institute here owned by Sinar Mas, one of Indonesia’s largest business conglomerates. The study plot he was visiting was managed without herbicides or insecticides; plantation workers weeded it by hand, and only in a small circle around each tree. As a result, many tall ferns and shrubs were growing beneath the canopy, creating a home for insects, spiders, and snakes. Many Indonesian planters would abhor this semiwilderness, worrying the understory would compete with oil palm trees for water and nutrients. Agung sees it differently. Allowing a luxuriant understory to grow in plantations can protect insects and some small mammals, such as the leopard cat—and ultimately benefit the oil palm trees as well. Sycanus and other predators control pests, for example, and other invertebrates improve the soil and pollinate the palms. Oil palm (Elaeis guineensis) is one of the most controversial crops today, because the plantations often replace tropical rainforests rich in biodiversity, depriving iconic species such as the orangutan of their habitats. Vast swaths of Indonesia and Malaysia are given over to the crop. But Agung and a growing number of other scientists say it’s time to work with oil palm companies—some of them in the crosshairs of environmental activists—to make the best of a bad situation….
2019-04-30. Imported wolves settle in as Lake Superior island teems with moose. By Christine Mlot, Science Magazine. [https://www.sciencemag.org/news/2019/04/imported-wolves-settle-lake-superior-island-teems-moose] Excerpt: Thirteen new radio-collared wolves are now scouting Isle Royale in Michigan and feasting on moose, whose numbers this winter reached 2060—the second highest estimate since ecologists began to study predators and prey on the island in 1958. The new wolves, imported to help restore the U.S. national park from overbrowsing by moose, are largely avoiding the territory of the remaining two wolves of the original population. Twenty female moose are also sporting radio collars, allowing biologists to watch both wolf and moose movements online. After 8 years essentially unfettered by predation because wolf numbers were so low, the moose population has been booming at 19% a year, according to data released today by Michigan Technological University (MTU) in Houghton. The new wolves are expected to check moose numbers and help restore balsam fir and other plants, according to National Park Service (NPS) planners. And the flood of GPS data is revealing “stuff we’ve never seen before,” says MTU wildlife ecologist Rolf Peterson, such as where moose congregate to feed on new spring growth. Peterson and his colleagues plan to chemically analyze the specific balsam fir trees moose eat to determine whether they choose twigs with compounds that may have anti-inflammatory properties….
2019-04-25. Australia Is Deadly Serious About Killing Millions of Cats. By Jessica Camille Aguirre, The New York Times. [https://www.nytimes.com/2019/04/25/magazine/australia-cat-killing.html] Excerpt: In the deep winter weeks of last July, Shane Morse and Kevin Figliomeni …in the darkness before dawn they began unloading poisoned sausage from their refrigerated truck. The sausage was for killing cats. …Morse and Figliomeni unpacked their boxes, filled with thousands of frozen sausages they produced at a factory south of Perth, according to a recipe developed by a man they jokingly called Dr. Death. It called for kangaroo meat, chicken fat and a mix of herbs and spices, along with a poison — called 1080 — derived from gastrolobium plants and highly lethal to animals, like cats, whose evolutionary paths did not require them to develop a tolerance to it. (The baits would also be lethal to other nonnative species, like foxes.) …a light twin-engine propeller Beechcraft Baron …traced a route over the landscape, its bombardier dropping 50 poisoned sausages every square kilometer. … These fatal airdrops owed their existence to Australia’s national government, which decided in 2015 to try to kill two million feral cats by 2020, out of grave concern for the nation’s indigenous wildlife — in particular, groups of small, threatened rodent and marsupial species for which cats have become a deadly predator….
2019-04-08. A 17-Foot Burmese Python Was Found in Florida. What Was It Even Doing There? By Sandra E. Garcia, The New York Times. [https://www.nytimes.com/2019/04/08/us/python-florida.html] Excerpt: A slithering, 17-foot Burmese python found at Big Cypress National Preserve in the Florida Everglades weighed 140 pounds and took four people to carry. What may have been even more unnerving (for conservationists, anyway) was that it contained 73 developing eggs. That’s because the Burmese python, as its name suggests, is a nonnative species in Florida that is considered invasive and harmful to the area’s ecology. Researchers at the preserve, as they have done with other female pythons, euthanized the huge snake and destroyed the eggs. “She is the largest python ever removed from Big Cypress National Preserve — and she was caught because of research and a new approach to finding pythons,” the preserve said on Facebook late last week. The researchers found the snake by using male pythons with radio transmitters to locate breeding females. …Burmese pythons can grow to about 23 feet and are native to South Asia. They found their way to Florida decades ago through people who imported them as pets. Many owners underestimate how large the python will grow, and sometimes they let the snakes loose when they can no longer take care of them. Female pythons have the ability to lay 100 eggs, and the snakes multiply quickly….
2019-01-30. Exploding demand for cashmere wool is ruining Mongolia’s grasslands. By Kathleen McLaughlin, Science Magazine. [https://www.sciencemag.org/news/2019/01/exploding-demand-cashmere-wool-ruining-mongolia-s-grasslands 0] Excerpt: …Essential to the identity and economy of Mongolia—more than half of the country’s 3 million people live there—the grasslands are under increasing threat from overgrazing and climate change. Multiple studies over the past decade have shown that the once lush Mongolian steppe, an expanse twice the size of Texas that is one of the world’s largest remaining grasslands, is slowly turning into a desert. An estimated 70% of all the grazing lands in the country are considered degraded to some degree. But a consortium of researchers is hoping data from space could help herders on the ground lighten their impact. …From 1940 to 2014, annual mean temperatures here have increased by 2.07°C, more than double the global average. Ten of the warmest years on record have occurred since 1997, while rainfall has decreased and seasonal weather patterns have shifted. This has exacerbated soil erosion, which has begun to alter the vegetation, a trend that projections show will intensify in the first half of the 21st century. Meanwhile, development, especially mining, has exponentially increased water usage. Twelve percent of rivers and 21% of lakes have dried up entirely. An increasing number of people, vehicles, and heavy equipment put additional stress on the land. But one factor stands out: overgrazing, which, according to a 2013 study by researchers at Oregon State University in Corvallis, has caused 80% of the recent decline in vegetation on the grasslands….
2019-01-01. A Rising Threat to Wildlife: Electrocution. By Rachel Nuwer, The New York Times. [https://www.nytimes.com/2019/01/01/science/wildlife-electrocution.html] Excerpt: Power lines and electrified fences are killing birds, monkeys, pangolins and even elephants in surprising numbers. South Africa is a country of ranches, farms, reserves and national parks, many surrounded by miles of electric fencing. The fencing keeps out unwanted animal and human intruders, and protects livestock and desirable wildlife. But the fencing also has a deadly, unintended side effect: It frequently kills smaller animals, particularly birds and reptiles that scientists are eager to conserve. Trip wires are often to blame. Positioned about half a foot off the ground, the wires are meant to send a deterring zap to hungry lions and crop-raiding bush pigs. But not all creatures respond by turning tail. Tortoises that hit a tripwire withdraw into their shells rather than retreat, while pangolins curl over the wire into a defensive ball. The animals stay put, shocked until their hearts give out. “Farmers will walk along fences and find six to eight dead tortoises in the space of 100 meters,” said Luke Arnot, a veterinary surgeon and lecturer at the University of Pretoria. “With tortoises, we tend to think of poaching and bush fires, but electric fences are as big, if not a bigger problem.” According to a 2008 study [http://wiredspace.wits.ac.za/jspui/bitstream/10539/7980/1/Beck%20Final%20MSc%20Dissertation.pdf 0], some 21,000 reptiles in South Africa are killed each year after coming into contact with electric fences….
2018-09-25. ‘Highly Aggressive’ Green Crabs From Canada Menace Maine’s Coast. By Melissa Gomez. [https://www.nytimes.com/2018/09/25/us/canadian-green-crabs-migration.html] Excerpt: …In the mid-1800s, European green crabs hitched a ride on boats and came to the United States. But over the past few years, a genetically different European green crab from Nova Scotia, Canada — one that is more combative and more destructive of ecosystems — has appeared off the coast of Maine. …The aggressive nature of the Canadian hybrid poses another problem for Maine, which already struggles to defend its soft-shell clam population from Maine green crabs. …Researchers worry that a changing climate and warming waters could make conditions more favorable for them….
2018-07-06. A fence built to keep out wild dogs has dramatically altered the Australian landscape. By Lakshmi Supriya, Science Magazine. Excerpt: Southern Australia’s Strzelecki Desert is home to two very different landscapes: an area of 10-meter-high sand dunes with patches of dense woody shrubs, and—just a few kilometers away—shorter and flatter dunes surrounded by sparse vegetation. The reason for the difference? Dingoes. That’s the conclusion of a study published this week in the Journal of The Royal Society Interface, in which researchers compared the landscape on either side of a 5000-kilometer-long wire mesh dingo fence. Built almost a century ago to keep Australia’s wild dogs from private land and livestock, the structure appears to have altered an entire ecosystem, the team found. When the researchers compared drone-captured images of the dunes and vegetation cover on either side of the fence to historical aerial photographs taken between 1948 and 1999, they discovered that there are about 60 more woody shrubs per hectare on the side of the fence with no dingoes than on the other side. The dunes on the nondingo side are also about 66 centimeters taller. The likely explanation, the team says, is that without a top predator like the dingo, smaller hunters such as foxes and cats have flourished, decimating prey species like hopping mice and rabbits. With fewer animals left to eat the plant seeds, the shrub cover has increased. The shrubs hold down sand and cause winds to skim over their tops, causing dunes to grow taller and carving the landscape differently on the two sides of the fence…. http://www.sciencemag.org/news/2018/07/fence-built-keep-out-wild-dogs-out-has-dramatically-altered-australian-landscape
2018-02-02. Dams nudge Amazon’s ecosystems off-kilter. By Barbara Fraser, Science. Summary: Once upon a time, thousands of dorados, a giant among catfish, would swim more than 3000 kilometers from the mouth of the Amazon River to spawn in Bolivia’s Mamoré River, in the foothills of the Andes. But the dorado, which can grow to more than 2 meters in length, is disappearing from those waters, and scientists blame two hydropower dams erected downstream a decade ago. As countries seek new energy sources to drive economic growth, a surge in dam construction on the eastern flank of the Andes could further threaten fish migration and sediment flows, scientists warn this week in Science Advances. The main consequence of proliferating dams is habitat fragmentation. The dorado’s disappearance suggests fragmentation is already taking a toll…. http://science.sciencemag.org/content/359/6375/508
2018-01-26. Moving in the Anthropocene: Global reductions in terrestrial mammalian movements. By Marlee A. Tucker et al, Science. Excerpt: Until the past century or so, the movement of wild animals was relatively unrestricted, and their travels contributed substantially to ecological processes. As humans have increasingly altered natural habitats, natural animal movements have been restricted. Tucker et al. examined GPS locations for more than 50 species. In general, animal movements were shorter in areas with high human impact, likely owing to changed behaviors and physical limitations. Besides affecting the species themselves, such changes could have wider effects by limiting the movement of nutrients and altering ecological interactions. Abstract: Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission…. http://science.sciencemag.org/content/359/6374/466
2017-12-05. Sometimes Seeing More Endangered Tigers Isn’t a Good Sign. By Douglas Quenqua, The New York Times. Excerpt: Sumatran tigers can’t seem to catch a break. This week, a study containing good news about the population of this endangered cat also carried a disclaimer that there was probably no cause for optimism. The new study, published Tuesday in Nature Communications, relied on images from more than 300 trap cameras as well as data from decades of similar studies. The authors reported that tiger density in Sumatra’s three largest protected forests increased 5 percent per year from 1996 to 2014, suggesting that Indonesia’s preservation efforts are slowly working. However, the increase was probably caused by an influx of tigers fleeing unprotected forests on the large western island in the Indonesian archipelago, where their numbers are dropping rapidly, the researchers said…. https://www.nytimes.com/2017/12/05/science/sumatran-tigers.html
2017-09-25. Pandas Are No Longer Endangered. But Their Habitat Is in Trouble. By Douglas Quenqua, The New York Times. Excerpt: One year after giant pandas graduated from endangered to “vulnerable,” a welcome designation after 28 years, Chinese scientists have sobering news: The animal’s natural habitat in China is in serious danger. In a study published in Nature Ecology & Evolution on Monday, researchers report that suitable panda habitats have significantly and steadily declined since 1990, the year the International Union for the Conservation of Nature first classified the animals as endangered. That could make any gain in China’s wild panda population a short-lived conservation victory. Logging, human encroachment, road construction and agriculture have conspired to divide panda habitats into tiny sections, a process known as fragmentation, the study said…. https://www.nytimes.com/2017/09/25/science/pandas-habitat-china.html
2016-09-08. We’ve destroyed one-tenth of Earth’s wilderness in just 2 decades. By Elizabeth Pennisi, Science. Excerpt: When most people think about conservation, they probably imagine saving the panda, or some other threatened creature, or maybe protecting whatever remains of its habitat. But James Watson thinks we’re missing the big picture. Large swaths of wilderness also really need our help, he and his colleagues report today. They have compared the extent of Earth’s wilderness areas in 1993 and 2009, documenting almost a 30% loss in South America and a 10% loss globally. Similar estimates in the past have focused on deforestation, but the new study looks at the disappearance of a broader range of wild landscapes. …Such unspoiled regions, scientists argue, are also critical for allowing the planet to cope with climate change. …Watson, a conservation biogeographer at the Wildlife Conservation Society based at the University of Queensland, St. Lucia, in Brisbane, Australia, and his colleagues earlier determined the extent of the “human footprint” on Earth by incorporating maps and data on crop lands, pastures, night lighting, railways, roadways, navigable waterways, population densities, and “built” environments, which included urban areas and other settlements. For most of these threats to wilderness, they had satellite and other data from the early 1990s and for the late 2000s. All but two of these pressures have increased in that time, Watson and his colleagues reported in a study last month in Nature Communications. (Roadways and waterways haven’t expanded noticeably.) Wilderness is defined as pristine landscapes mostly free of human disturbances, including roads. …By 2009, about 23% of Earth’s land remained as wilderness—about 30.1 million square kilometers spread mostly across North America, North Asia, North Africa, and Australia, they conclude today in Current Biology. That’s 3.3 million square kilometers less than in 1993, …. South America has lost almost 30% of its wilderness in that time and Africa has lost 14%…. http://www.sciencemag.org/news/2016/09/we-ve-destroyed-one-tenth-earth-s-wilderness-just-2-decades
2016-04-27. Monarchs Need Better Pit Stops on Their Epic Journeys. By Susan Cozier, Natural Resources Defense Council. Excerpt: Projects across the Midwest are trying to bring milkweed and nectar-filled flowers back to the landscape. …In the past 25 years, monarch numbers have taken a nosedive, plummeting more than 90 percent due primarily to habitat destruction. The butterflies migrate back and forth across North America, fluttering south to Mexico for the winter and north as far as Canada in spring and summer. The round-trip journey spans three butterfly generations or more, and to make it, they need plants: those that provide nectar to fuel them and those that help them make more monarchs. Milkweed is the only plant on which monarchs lay eggs and is crucial to the species’s survival. …[Mary] Galea’s project, part of the Pollinator Partnership, is just one of many looking at how we can revive monarch populations across the United States. The plants Galea and others are growing could prove critical to monarch populations in Ohio. Real success, however, won’t rely only on the greenery in our backyards, parks, and roadsides; we’ll also have to address what chemicals we spray on farm crops. Once upon a time, milkweed grew naturally on farms, between fields of corn and soybeans. But farmers, under pressure to increase their yields, plowed fallow fields and started growing genetically modified crops designed to resist the powerful herbicide glyphosate (marketed as Roundup). Knowing these “Roundup ready” crops could withstand widespread application of the herbicide, farmers would spray entire fields with the chemical instead of targeting their crops directly. Now, native plants, such as milkweed, die right along with the unwanted weeds. As the milkweed went, so went the monarchs. By some estimates, the amount of milkweed along the monarchs’ midwestern path fell nearly 60 percent between 1999 and 2010. And we’re still losing one to two million acres of habitat a year, thanks to development, over-mowing, and pesticides, says Chip Taylor, a prominent monarch researcher at the University of Kansas and head of Monarch Watch…. https://www.nrdc.org/onearth/monarchs-need-better-pit-stops-their-epic-journeys
2016-02-29. Invasive Species Aren’t Always Unwanted. By Erica Goode, The New York Times. Excerpt: Invasive species are bad news, or so goes the conventional wisdom, encouraged by persistent warnings from biologists about the dangers of foreign animals and plants moving into new territories. Conservation organizations bill alien species as the foremost threat to native wildlife. Cities rip out exotic trees and shrubs in favor of indigenous varieties. And governments spend millions on efforts to head off or eradicate biological invaders. …But a growing number of scientists are challenging this view, arguing that not all invasive species are destructive; some, they contend, are even beneficial. The assumption that what hails from elsewhere is inherently bad, these researchers say, rests more on xenophobia than on science. …Many common animals, plants and insects are not native to the environments in which they are now found. Take this quiz and learn more about the living things that surround you. …“We’re actually moving plants and animals around the world all the time,” he said. “We have been for centuries.” …Eradicating most invasive species is virtually impossible in an era of globalization, they note. And as climate change pushes more species out of their home ranges and into new areas, the number of so-called invaders is likely to multiply exponentially. …Some alien species are undeniably harmful, a fact that neither Dr. Davis nor others who share his view dispute. The fungus that causes chestnut blight, for example, decimated thousands of trees and changed the American landscape in the early 1900s. The Zika virus is invading new regions, carried by infected mosquitoes that some say are being driven northward by warmer temperatures. …In a paper published last month in the journal Conservation Biology, two scientists in California, Michael P. Marchetti and Tag Engstrom, describe the “paradox” of species that are under threat in their native range but are viewed as invasive in other places they have settled…. http://www.nytimes.com/2016/03/01/science/invasive-species.html
2015-04-05. The Snake That’s Eating Florida. By Clyde Haberman, The New York Times. Excerpt: [video: Pets Gone Wild] …In South Florida, wildlife officials have struggled for years with tens of thousands of the creatures: specifically, a species known as the Burmese python, an interloper from Southeast Asia that has taken up what looks like permanent residence in Everglades National Park and other areas of the state. …At full maturity, a Burmese python routinely reaches lengths of 12 feet or more. Twenty-footers weighing 250 pounds are not unheard-of. The pythons are prodigious breeders, with voracious appetites to match. They are believed to have eaten their way through the Everglades, bringing about startling changes in the ecosystem. Some mammals native to those marshes, like foxes and rabbits, seem to have disappeared, researchers say. Other species — among them raccoons, deer, opossums and bobcats — are close to being wiped out. Pythons that migrated from the mainland to Key Largo have put indigenous wood rats in mortal peril. …One issue with Burmese pythons is that people cavalierly bought them when they were maybe a foot long. In short order, those little fellows grew to eight feet, 12 feet, 16 feet. Talk about buyer’s remorse. Unable to deal with these giants, owners often dumped them wherever seemed feasible…. http://www.nytimes.com/2015/04/06/us/the-burmese-python-snake-thats-eating-florida.html
2015-03-23. Shrinking habitats have adverse effects on world ecosystems–and ultimately people. NSF. Excerpt: An extensive study of global habitat fragmentation–the division of habitats into smaller and more isolated patches–points to major trouble for the world’s ecosystems. The study shows that 70 percent of existing forest lands are within a half-mile of forest edges, where encroaching urban, suburban and agricultural influences can cause harmful effects such as losses of plant and animal species. …”The results are stark,” said Doug Levey, program director in NSF’s Division of Environmental Biology and a co-author of the paper. “No matter the place, habitat or species, habitat fragmentation has large effects, which grow worse over time.” …”It’s no secret that the world’s forests are shrinking, so we asked about the effects of this habitat loss and fragmentation on the remaining forests,” said Nick Haddad, a biologist at North Carolina State University and corresponding author of the paper. “The results were astounding,” he said. “Nearly 20 percent of the world’s remaining forests are the distance of a football field–or about 100 meters–away from forest edges. Seventy percent of forest lands are within a half-mile of forest edges. That means almost no forests can really be considered wilderness.” …”The initial effects were unsurprising,” Haddad said. “But I was blown away by the fact that these negative effects became even more negative with time. Some results showed a 50 percent or higher decline in plant and animal species over an average of just 20 years. …Haddad points to some possible ways of mitigating the effects of fragmentation: conserving and maintaining larger areas of habitat; using landscape corridors, or connected fragments that are effective in maintaining higher biodiversity and better ecosystem function; increasing agricultural efficiency; and focusing on urban design efficiencies. “Ultimately, habitat fragmentation has harmful effects that will also hurt people,” said Haddad. “This study is a wake-up call to how much we’re affecting ecosystems–including areas we think we’re conserving.”… http://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=134468&WT.mc_id=USNSF_1.
2014-10-13. A Threat Is Seen in Pumas’ Isolation. By Douglas QuenQua, The New York Times. Excerpt: The isolating effects of human development are causing a sharp decline in genetic diversity among mountain lions in Southern California, a new study says. Researchers from the University of California, Davis, collected DNA samples from more than 350 mountain lions throughout California and found that animals separated by little more than a highway have far less genetic material in common than they did just 80 years ago, suggesting that there is far less interbreeding among populations. Pumas in the Santa Ana Mountains — effectively fenced in by Interstate 15 to the east, the Pacific Ocean to the west and Los Angeles to the north — displayed lower genetic diversity …So severe is their isolation that the Santa Ana pumas have more in common genetically with lions 400 miles to the north than their neighbors in the Santa Monica Mountains. … “Genetically diverse populations are better able to handle whatever nature or humans throw at them, like climate change or disease,” said Dr. Ernest, a geneticist now at the University of Wyoming. “If mountain lions lose that genetic diversity, they lose that resilience.”…. By Douglas Quenqua, The New York Times. http://www.nytimes.com/2014/10/14/science/a-threat-is-seen-in-pumas-isolation.html?ref=science.
2014-04-27. A variety of California kingsnake is wreaking havoc in Canary Islands. Excerpt: An albino variety of California kingsnake popular in the pet trade has infested the Canary Islands, decimating native bird, mammal and lizard species that have had no time to evolve evasive patterns in what was once a stable ecology northwest of Africa. …Canary Island biologists fear that the snakes may be nibbling three native species of gecko, skink and giant lizard into extinction. …”Most control programs for invasive reptiles are initiated long after the problem has gotten out of hand,” Reed said. “Unfortunately, this sort of thing will probably become more common as international borders fall, incomes rise and more people get interested in owning exotic pets.”… http://www.latimes.com/science/la-me-kingsnake-20140428,0,2901782.story#ixzz30yhbHq5B. By Louis Sahagun, Los Angeles Times.
2014-03-24. Carp(e) Diem: Kentucky Sends Invasive Fish To China. Excerpt: …The invasive Asian carp has now been found in 12 states and in the Great Lakes watershed, gobbling up native fish, jumping aggressively into boats and reproducing like crazy. Researchers have tried various ways to slow the spread of the fish as it prowls other waterways. …So now a processing plant in Kentucky is trying the latest method of Asian carp disposal: sending them to China. …Angie Wu ships them to her native country — China — where they are a prized food. “There are a lot [of carp] in China but most of them are farmed … not very clean as here,” she says. Wu has shipped more than a half-million pounds of processed carp to China. …Asian carp hasn’t caught on in U.S. restaurants, but that hasn’t stopped Kentucky from trying to teach people how to prepare it. …The state has also hosted tastings to show people that when you fry Asian carp in cornmeal, it’s not that different from catfish. …one longtime fishermen and distributor, Ronnie Hopkins…says it is possible to make a living on Asian carp, but it’s not easy. He says native fish sell for about 60 cents a pound — the abundant carp go for just 10 cents a pound … and that’s if he can find a local buyer. “I wish the state would get more involved and maybe use it as product in our schools. We’re buying from other countries and other states right now when we’ve got an abundance of fish we could use,” says Hopkins…. http://www.npr.org/blogs/thesalt/2014/03/24/293846571/carp-e-diem-kentucky-sends-invasive-fish-to-china. Whitney Jones, NPR.
2014-03-16. Officials give up on evicting pythons — big but nearly invisible in the wild — from Everglades. Excerpt: …Only in Florida can a search for one invasive monster lead to the discovery of another. …recently, a group of volunteers called Swamp Apes was searching for pythons in Everglades National Park when it stumbled on something worse: a Nile crocodile, lurking in a canal near Miami suburbs. It was an all-points alarm, prompting an emergency response by experts from the national park, the Florida Fish and Wildlife Conservation Commission and the University of Florida. They joined the Swamp Apes and wrestled the reptile out of the canal. Nile crocs are highly aggressive man-eaters known to take down huge prey in Africa, and officials worried that the one in the canal might be breeding in the swamp since it was first spotted two years ago. Worrying is what Florida wildlife officials often do when it comes to invasive species. The state is being overrun by animals, insects and plants that should not be there, costing Floridians half a billion dollars each year in, among other things, damaged orange groves, maimed pets and dead fish in water where plants have depleted the oxygen. …Native Florida alligators are already in a death match with giant Burmese pythons and other python species to sit atop the food chain. On top of that is a rogues’ gallery of bad-to-the-bone lizards, fish and frogs. They include the Argentine tegu, which eats sea turtle eggs; the Nile monitor lizard, which kills house pets; the Cuban tree frog, which dines on other frogs; and the greedy lionfish, which is eating scores of native fish. …Up to 100,000 pythons are estimated to be living in the Everglades, and more than 1,500 thrill-seekers, amateurs and skilled hunters who flocked to the event from across the country caught only 68. http://www.washingtonpost.com/national/health-science/big-but-nearly-invisible-in-the-wild-officials-give-up-on-evicting-pythons-from-everglades/2014/03/16/58cab268-aa37-11e3-8599-ce7295b6851c_story.html. Darryl Fears, Washington Post.
2014-02-24. Science Takes On a Silent Invader. Excerpt: Since they arrived in the Great Lakes in the 1980s, two species of mussels the size of pistachios have spread to hundreds of lakes and rivers in 34 states and have done vast economic and ecological damage. …the quagga and zebra mussels, have disrupted ecosystems by devouring phytoplankton, the foundation of the aquatic food web, and have clogged the water intakes and pipes of cities and towns, power plants, factories and even irrigated golf courses. …Daniel P. Molloy, an emeritus biologist at the New York State Museum in Albany …Leading a team at the museum’s Cambridge Field Research Laboratory in upstate New York, … discovered a bacterium, Pseudomonas fluorescens strain CL145A, that kills the mussels but appears to have little or no effect on other organisms. …New York State has awarded a license to Marrone Bio Innovations, a company in Davis, Calif., to develop a commercial formulation of the bacterium. The product, Zequanox, has been undergoing tests for several years, with promising results …Zequanox killed more than 90 percent of the mussels in a test using tanks of water from Lake Carlos in Minnesota …A control group of freshwater mussels, unionids from the Black River in Wisconsin, were unharmed. …Natives of Eastern Europe …zebra and quagga mussels began moving up the Volga River toward Western Europe 200 years ago. …Both species are thought to have arrived in North America in the ballast of trans-Atlantic cargo ships…. http://www.nytimes.com/2014/02/25/science/science-takes-on-a-silent-invader.html. Robert H. Boyle, The New York Times.
2012 Jun 07. Warming nears point of no return, scientists say. By David Perlman, SF Gate. Excerpt: The Earth is reaching a “tipping point” in climate change that will lead to increasingly rapid and irreversible destruction of the global environment unless its forces are controlled by concerted international action, an international group of scientists warns. Unchecked population growth, the disappearance of critical plant and animal species, the over-exploitation of energy resources, and the rapidly warming climate are all combining to bring mounting pressure on the Earth’s environmental health…scientists from five nations, led by UC Berkeley biologist Anthony Barnosky, report their analysis Thursday in the journal Nature….
2011 July 14. Ecosystems take hard hit from loss of top predators. By Sarah Yang and Robert Sanders, UC Berkeley News Center. Excerpt: BERKELEY — A paper reviewing the impact of the loss of large predators and herbivores high in the food chain confirms that their decline has had cascading effects in marine, terrestrial and freshwater ecosystems throughout the world. The paper, published in the July 15 issue of the journal Science by an international team of 24 researchers, presented evidence highlighting the reverberating – and often unexpected – effects the loss of “apex consumers” have had not only on immediate prey species, but also on the dynamics of fire, disease, vegetation growth, and soil and water quality…
2011 May 31. Groundwater Depletion Is Detected From Space. By Felicity Barringer, The NY Times. Excerpt: Scientists have been using small variations in the Earth’s gravity to identify trouble spots around the globe where people are making unsustainable demands on groundwater, one of the planet’s main sources of fresh water…
…Jay S. Famiglietti, director of the University of California’s Center for Hydrologic Modeling here, said the center’s Gravity Recovery and Climate Experiment, known as Grace, relies on the interplay of two nine-year-old twin satellites that monitor each other while orbiting the Earth, thereby producing some of the most precise data ever on the planet’s gravitational variations. The results are redefining the field of hydrology, which itself has grown more critical as climate change and population growth draw down the world’s fresh water supplies….
…Yet even as the data signals looming shortages, policy makers have been relatively wary of embracing the findings….
2011 March 21. As Larger Animals Decline, Forests Feel Their Absence. By Sharon Levy, Environment 360 (Yale). Excerpt: …Today native Mauritian plants, under siege from a tide of invasive competitors and predators, hang on only in a few small conservation management areas. Even where invasive plants are laboriously weeded out by hand, large-fruited native tree populations are dwindling because of a lack of fruit-eating animals to disperse the trees’ seeds….
…As part of a restoration effort on Ile aux Aigrettes, an uninhabited islet off the Mauritius coast, the Mauritius Wildlife Federation and the Mauritius government in 2000 introduced giant Aldabra tortoises to test whether the tortoises could help revive native vegetation. The tortoises are now dispersing the seeds of several native plants and are knocking back an invasion of the exotic tree, Leuceana leucocephala, by devouring its seedlings….
2010 September 27. Old Trees May Soon Meet Their Match. By Jim Robbins, New York Times. Excerpt: For millenniums, the twisted, wind-scoured bristlecone pines that grow at the roof of western North America have survived everything nature could throw at them, from bitter cold to lightning to increased solar radiation.
Living in extreme conditions about two miles above sea level, they have become the oldest trees on the planet.
… Now, however, scientists say these ancient trees may soon meet their match in the form of a one-two punch, from white pine blister rust, an Asian fungus that came to the United States from Asia, via Europe, a century ago, and the native pine bark beetle, which is in the midst of a virulent outbreak bolstered by warming in the high-elevation West.
…The pest and the disease working together are especially deadly. “Blister rust kills young trees rapidly,” Dr. Schoettle said. “The mountain pine beetle only kills the larger trees, but those are the trees that produce the seeds. So when you have a combination of blister rust and the beetle, that severely constrains recovery of the population.”
The long-term strategy that biologists are banking on to save the bristlecones from dying out completely is finding the few trees that are resistant to the fungus and growing their seeds into rust-resistant seedlings.
…The bristlecones face even more fundamental changes. Warmer temperatures are significantly altering ecosystems… Some ecologists think that as warming continues, species that live at the top of mountains may no longer have a niche and simply disappear, something that has been called the “rapture hypothesis.”
…“The key to the bristlecone is that they grow in a rigorous environment,” said Ronald Lanner, a retired forest biologist who studied bristlecones and has written a book about them, “and that environment is also rigorous to their pests.”
2010 May 7. Pythons in Florida Stalked by Hunters and Tourists Alike. By Damien Cave, NY Times. Excerpt: FLORIDA CITY, Fla. — Thousands of Burmese pythons, the offspring of former pets, have invaded the Everglades, eating birds, bunnies, even alligators. It has gotten so bad that Congress is considering an outright ban on buying or selling nine kinds of giant snakes.
But an odd thing has happened here in the swamp: the pythons have become celebrities. The snakes are fast becoming an element of Florida lore, attracting “oohs” and “ahhs” from tourists, along with groans from biologists and even python hunters like Bob Freer.
“It’s a little frustrating and very strange,” said Mr. Freer, who figures that his 40 captured pythons — most of which he has euthanized — make him the state’s top private hunter. “They’re asking about pythons that don’t even belong here, instead of alligators.”
Trouble is, the newfound fascination obscures what biologists and Mr. Freer describe as a serious problem. In their view, python proliferation — still significant despite a cold winter that might have killed half the population — is simply the sexiest example of widespread disrespect for pets and the wilderness….
2009 Fall. Hardrock Headache. By Alice Tallmadge, Forest Magazine. Excerpt: …There’s no doubt that hardrock mining helped build the West. It lured the curious and the inventive, the brave and the greedy, the visionary and the hopeful across the plains and into the mountains of the arid West. The 1872 Mining Law made land and mining cheap and laid out a welcome mat for mining into the twenty-first century. Mining generated communities, agriculture, railroads and commerce and built an industry that provided a livelihood for thousands.
Now we know the earth exacts a huge price for the taking of its minerals. Thousands of acres of public lands across the West are affected by acid mine drainage from abandoned mines, an insidious mining residue that can appear years after a mine has been shuttered and can last for decades. In addition, tunnel openings, vertical shafts and mineral-laced pools pose safety hazards for humans and wildlife.
Today, thousands of abandoned hardrock mining sites are located in the western United States—19,000 inventoried sites on Bureau of Land Management land and about 40,000 on national forest land. Thousands more sites have not yet been inventoried. Because mining companies aren’t required to post bonds for cleanup, taxpayers are footing the bill for billions of dollars in reclamation costs that will, in some cases, be required for decades….
* The Mine Next Door by Scott Streater
* Mining for Reform by Joshua Zaffos
* Cleanup at the Blue Ledge by Alice Tallmadge
* Reclaim and Reuse by Scott Streater
2009 August 12. NASA RELEASE: 09-185. Satellites Unlock Secret to Northern India’s Vanishing Water. Excerpt: WASHINGTON — Using NASA satellite data, scientists have found that groundwater levels in northern India have been declining by as much as one foot per year over the past decade. Researchers concluded the loss is almost entirely due to human activity.
More than 26 cubic miles of groundwater disappeared from aquifers in areas of Haryana, Punjab, Rajasthan and the nation’s capitol territory of Delhi, between 2002 and 2008. This is enough water to fill Lake Mead, the largest manmade reservoir in the United States, three times.
A team of hydrologists led by Matt Rodell of NASA’s Goddard Space Flight Center in Greenbelt, Md., found that northern India’s underground water supply is being pumped and consumed by human activities, such as irrigating cropland, and is draining aquifers faster than natural processes can replenish them….
The finding is based on data from NASA’s Gravity Recovery and Climate Experiment (GRACE), a pair of satellites that sense changes in Earth’s gravity field and associated mass distribution, including water masses stored above or below Earth’s surface. As the twin satellites orbit 300 miles above Earth’s surface, their positions change relative to each other in response to variations in the pull of gravity.
Changes in underground water masses affect gravity enough to provide a signal that can be measured by the GRACE spacecraft. After accounting for other mass variations, such changes in gravity are translated into an equivalent change in water.
…”We don’t know the absolute volume of water in the northern Indian aquifers, but GRACE provides strong evidence that current rates of water extraction are not sustainable,” said Rodell. “The region has become dependent on irrigation to maximize agricultural productivity. If measures are not taken to ensure sustainable groundwater usage, the consequences for the 114 million residents of the region may include a collapse of agricultural output and severe shortages of potable water.”…
2009 August 8. Avian Silence: Without Birds to Disperse Seeds, Guam’s Forest Is Changing. By Brendan Borrell, Scientific American. Excerpt: The forest on Guam is silent.
Sometime after World War II the brown tree snake arrived as a stowaway on this U.S. Pacific island territory 6,100 kilometers west of Hawaii. It has since extirpated 10 of the island’s 12 native forest bird species. The remaining forest birds have been relegated to small populations on military bases, where the snakes are kept in check. In the first study of its kind, a rugby-playing researcher named Haldre Rogers is documenting how the forest itself is changing.
…Of the approximately 40 species of trees on Guam, about 60 to 70 percent once depended on birds to eat their fruits and disperse their seeds. The birds may have just nicked and dropped seeds somewhere along a flight path, or they could have swallowed the seeds, digested their tough coats, and pooped them out with a splatter of high-nitrogen urea.
Rogers went to neighboring islands that still have birds along with many of the same trees, collected seeds from the tree Premna obtusifolia, and brought them back to grow in a greenhouse on Guam. She found that seeds handled by birds are twice as likely to germinate as seeds that simply land on the forest floor. They also germinate about 10 days more quickly, giving them a better shot at evading seed-destroying rodents or fungi.
In another experiment, Rogers has found that seeds on Guam now always land directly in the shade of the mother tree and always have an intact seed coat. But seeds from neighboring islands that still have birds can sometimes end up 10 to 20 meters away from the mother tree, where they are more likely to find a sunny niche with fewer enemies. About 80 percent of these have had their seed coat removed, meaning they can germinate more quickly….
…”The brown tree snake is held up as textbook example of how a destructive invasive species can eradicate birds,” she says. “This shows that the effects of introduced predators reverberate through the ecosystem.”
2009 August 1. An Underwater Fight Is Waged for the Health of San Francisco Bay. By Malia Wollan, The NY Times. Excerpt: SAN FRANCISCO — Chela Zabin will not soon forget when she first glimpsed the golden brown tentacle of the latest alien to settle in the fertile waters of San Francisco Bay.
…The tentacle in question was that of an Asian kelp, Undaria pinnatifida, a flavorful and healthful ingredient in miso soup and an aggressive, costly intruder in waters from New Zealand to Monterey Bay.
The kelp, known as wakame (pronounced wa-KA-me), is on a list of “100 of the World’s Worst Invasive Alien Species,” compiled by the Invasive Species Specialist Group. Since her discovery in May, Dr. Zabin and colleagues have pulled up nearly 140 pounds of kelp attached to pilings and boats in the San Francisco Marina alone.
Every year the damage wrought by aquatic invaders in the United States and the cost of controlling them is estimated at $9 billion, according to a 2003 study by a Cornell University professor, David Pimentel, whose research is considered the most comprehensive. The bill for controlling two closely-related invasive mussels — the zebra and the quagga — in the Great Lakes alone is $30 million annually, says the United States Federal Aquatic Nuisance Species Task Force.
Many scientists say that San Francisco Bay has more than 250 nonnative species, like European green crab, Asian zooplankton and other creatures and plants that outcompete native species for food, space and sunlight….
2009 July 6. Some See Beetle Attacks on Western Forests as a Natural Event. By JIM ROBBINS, The NY Times. Excerpt: MISSOULA, Mont. — When Ken Salazar — then a senator from Colorado, now secretary of the interior — called the attack on millions of acres of pine forests by the bark beetle the Katrina of the West, he was expressing the common view of the explosive growth of the beetles as an unmitigated disaster.
But not everybody sees it that way. Some environmentalists and scientists support the beetles. While they acknowledge the severity of the problems the beetles are causing, they argue that the insects, which kill only mature trees larger than five inches in diameter, are a natural phenomenon, like forest fires, and play a vital ecological role.
“It’s not the end of the forests, and they are not destroyed,” said Diana L. Six, a professor of forest entomology and pathology at the University of Montana here, who has studied the beetle for 16 years, as she walked in a beetle-infected forest near here recently .
“Lodge pole pine evolved to go out with a stand-replacing event, such as fire or beetles, then regenerate really quickly,” she said. “When they hit 80 or 90 years of age all of a sudden the beetles become a player — the trees are big enough for the beetles to attack. They reset the clock on the stand.”
…Nothing can or should be done to halt the spread of the beetle, experts say. After they kill the mature trees, the soil becomes more fertile as nitrogen levels increase, sometimes tripling. The growth rate of surviving trees increases when the infestation ends. After dead trees fall over or burn, grass grows and provides elk habitat, and slightly more diverse forests rise up.
…Both Dr. DeNitto and Dr. Six allow that the current outbreak is not entirely natural. Human intervention in the form of fire suppression and large-scale clear cuts mean that many forests are simultaneously vulnerable.
…The major human-caused element of the current outbreak, though, is a warmer climate, which has opened new territory to the beetles. And this has caused some experts to view the beetle infestations as unnaturally severe….
2009 June 15. An Unsightly Algae Extends Its Grip to a Crucial New York Stream. By Anthony DePalma, The NY Times. Excerpt: SHANDAKEN, N.Y. — The Esopus Creek, a legendary Catskill Mountain fly fishing stream that is an integral part of New York City’s vast upstate drinking water system, is one of the latest bodies of water to be infected with Didymosphenia geminata, a fast-spreading single-cell algae that is better known to fishermen and biologists around the world as rock snot.
…Didymo has a natural tendency to grow upstream in fast-moving rivers and creeks, but it can spread by clinging to fishing equipment, especially the felt-bottom waders that fly fishermen use to keep from slipping on river bottoms.
Didymo is considered native to parts of North America, where it was found in higher elevations with cold, nutrient-poor waters. But in the last 20 years, the single-celled diatom seems to have morphed into a more aggressive invasive species, spreading from British Columbia across the continent to New York.
Unlike other algae, which float on the surface, Didymo clings to rocks on the bottom of rivers, streams and lakes. At times it grows furiously in blooms that can cover a river bottom from bank to bank, smothering the stone flies, worms and other organisms that trout and other sport fish live on….
2009 February 16. The Unintended Consequences of Changing Nature’s Balance. By Elizabeth Svoboda, The NY Times. Excerpt: With its craggy green cliffs and mist-laden skies, Macquarie Island — halfway between Australia and Antarctica — looks like a nature lover’s Mecca. But the island has recently become a sobering illustration of what can happen when efforts to eliminate an invasive species end up causing unforeseen collateral damage.
In 1985, Australian scientists kicked off an ambitious plan: to kill off non-native cats that had been prowling the island’s slopes since the early 19th century. The program began out of apparent necessity — the cats were preying on native burrowing birds. Twenty-four years later, a team of scientists from the Australian Antarctic Division and the University of Tasmania reports that the cat removal unexpectedly wreaked havoc on the island ecosystem.
With the cats gone, the island’s rabbits (also non-native) began to breed out of control, ravaging native plants and sending ripple effects throughout the ecosystem….
“Our findings show that it’s important for scientists to study the whole ecosystem before doing eradication programs,” said Arko Lucieer, a University of Tasmania remote-sensing expert… “There haven’t been a lot of programs that take the entire system into account. You need to go into scenario mode: ‘If we kill this animal, what other consequences are there going to be?’ ”….