A baby cao vit gibbon learns to search for food. Photo: Zhao Chao 赵超, Fauna and Flora International

You probably haven’t heard of the world’s second rarest ape, the cao vit gibbon. Scientists know of only one place the species still lives in the wild. In the 1960s, things got so bad for the cao vit gibbon that the species was declared extinct. But in 2002, to the surprise and elation of conservationists, the animals—whose shaggy coats can be a fiery orange or jet black—turned up along Vietnam’s remote northern border. Several years later, a few gibbons were found in China, too.

Also known as the eastern black-crested gibbon, the cao vit gibbons once covered an expanse of forest spanning from southern China and northern Vietnam just east of the Red River, but today only about 110 individuals survive. This gibbon is highly inclined to stick to the trees—in a previous study, during more than 2,000 hours spent observing gibbons in the field, researchers saw only once and very briefly one young male cao vit gibbon come down from the canopy and walk on a rock for a few seconds. Population surveys based on watching the animals in the branches reveal that the gibbons live in 18 groups scattered throughout the area. That makes it the second least populous species of ape, just after the Hainan gibbon, another type of extremely rare gibbon living in the same area of Asia.

In 2007 and 2009, Vietnam and then China hustled to establish special protected areas dedicated to preventing the cao vit gibbon’s extinction. Much of the area surrounding the remaining populations of gibbons is quickly being converted to agricultural fields and pasturesor cut down to make charcoal to sell and use at home, a common practice in the area. Hunting—though illegal—is also an issue, as exotic wild meat dinners are popular with locals in the region.

For an endangered species to recover rather than just survive, it needs to grow in numbers. But any given patch of land can only support so many animals given the amount of food and space that’s available. If populations exceed this threshold—called a carrying capacity—then animals will either starve, get picked off by predators or have to move somewhere else. 

Researchers from Dali University in Yunnan, the Chinese Academy of Sciences in Kunming and the Chinese Research Academy of Environmental Sciences in Beijing wanted to find out how much of the protected forest the cao vit gibbons had expanded into, and also how many animals that pocket of land could eventually support. To answer this question, they turned to high-resolution satellite images, describing their results in the journal Biological Conservation.

Once they acquired aerial images of the gibbons’ habitat, they classified it into forest, scrub, shrub land and developed areas. This was important because gibbons can only live high in forest canopies, meaning the latter three categories were out of bounds for potentially supporting the animals. Overall, the area could be divided into five different zones that were split apart by either roads or rivers. From there, the researchers plugged the data into computer models that ranked possible gibbon habitat from high to low quality.

Habitat quality over the five zones the researchers identified. Stars mark sites where gibbons currently live. Image from Fan et al., Biological Conservation

Their results revealed several bits of news, some good and some bad. First, from the models it seems that 20 groups of gibbons could eventually live in the protected forest areas before the population reaches its carrying capacity threshold. However, as human development creeps closer and closer, that disturbance could lower that figure. As things stand, the gibbons will likely reach their carrying capacity in the current habitat in 15 years, which doesn’t bode well for building up the species’ numbers.

There are a couple options. The protected area isn’t all great habitat, it turns out. Some of it is just mediocre for gibbons. If that span of forest could be improved, it could eventually support up to 26 groups of animals. The researchers also identified two other potential areas where gibbons could live if they could somehow manage to travel there (no gibbon has ever been known to cross a river or a road). But these patches of welcoming forest, located in Vietnam, are not protected, so they likely will not remain forests for long. If the government decided to protect those areas, the researchers write, they could serve as places for cao vit gibbons to live in the future, especially if narrow corridors of trees connecting the two areas were protected and restored as well.

If these patches of forest were protected, gibbons would not be the only species to benefit. Numerous other species of primates and monkeys, civets, pangolins, porcupines, birds, bats and many more depend upon those last remaining jungle habitats for survival. “In summary, the last remaining population of cao vit gibbon is nearing its carrying capacity in the current remaining forest patch,” the authors write. “Forest protection and active forest restoration using important food tree plantings to increase habitat quality and connectivity should be the most critical part of the ongoing conservation management strategy.”

A bull male forest elephant in Gabon. A new study published in the PLOS ONE shows that African forest elephants are being poached into extinction. Photo by Elizabeth M. Rogers

When you think of an elephant, you probably picture a big-tusked bull stampeding through vast African grasslands. But there are more to elephants than this run-of-the-mill savannah variety. The African forest elephant—recently declared a distinct species from its plains-dwelling cousin–lives exclusively in the forests of Central Africa. Males rarely exceed 8 feet in height, compared to about 13 feet for savannah elephants–all the better for navigating through the jungle trees. They eat mostly fruit, and researchers think they play a key role in spreading seeds and shaping the forest’s environment and structure through their comings and goings.

But like many other animals living in Africa and Asia, this unique species is in decline as a result of rampant poaching for its ivory and loss of its forest habitat to human development. A new study led by the Wildlife Conservation Society and published in PLoS One puts those threats into perspective, and the news is not good. The situation for forest elephants is much worse than we thought, the paper announces, and unless we act quickly, the survival of these miniature elephants is in jeopardy.

Until now, conservationists had little idea of where exactly forest elephants live and how many of them there are. A team of 62 researchers from African, Europe and North America–the authors of the study–pooled their expertise and research efforts to figure out this basic information. Without these data, organizations such as the International Union for the Conservation of Nature (IUCN) cannot properly assess whether a species qualifies as endangered or not.

From 2002 to 2011, the team members conducted more than 80 forest elephant surveys in the jungles of Central Africa, focusing on five countries–Cameroon, Congo, the Central African Republic, the Democratic Republic of Congo, and Gabon. The scientists traveled on foot, covering around 13,000 kilometers of jungle. To determine elephant presence and density, the researchers set up transects to sample elephant dung, collecting more than 11,000 samples in total. Based on the amount of dung found, they extrapolated estimates of elephant population within a given area.

Their survey results were startling. They found “a widespread and catastrophic decline” of forest elephants, they write, corresponding to about a 62 percent decrease in forest elephant population size between the nine years of their survey. The elephants lost around 30 percent of their range during that time period, and they occupy just 25 percent of their potential forest habitat. The authors say that the population of forest elephants is now less than 10 percent of what it could be, given the extent of its habitat.

The paper conservatively estimates that around half a million forest elephants roamed Central Africa in the 1930s, but now 80 percent have been lost, leaving the population at an estimated 100,000 animals at most. In the Democratic Republic of Congo’s protected Okapi Faunal Reserve, for example, 5,100 elephants—75 percent of the park’s population—were killed over the past 15 years. In Gabon’s Minkébé National Park, officials announced earlier this year that roughly 11,000 forest elephants have been poached since 2004. The paper puts these reported losses into broad perspective.

“This is the first range-wide, data-driven study confirming that Central Africa is hemorrhaging elephants on an unprecedented scale,” said Samantha Strindberg, a researcher at the Wildlife Conservation Society and one of the study’s lead authors, in a statement. “The analysis confirms what conservationists have feared: the rapid trend towards extinction–potentially within the next decade–of the forest elephant, according to the authors.”

In the last few years, poaching for ivory and other wildlife products has escalated. Analyses performed by the Elephant Trade Information System and the Monitoring the Illegal Killing of Elephants program–both maintained by the Convention on International Trade in Endangered Species–confirmed that this escalation in illegal trade is largely due to a strong demand for and increase in value of ivory in China, where ivory carvings are prized and ivory powder is sold as a folk cure for cancer. The black market for ivory is estimated to have netted more than $264 million over the past decade.

A cache of illegal ivory goods confiscated New York City last year were worth an estimated $2 million. Photo via Manhattan District Attorney’s Office.

While this problem is typically associated with slain savannah elephants, the growing crisis increasingly applied to forest elephants as well. In addition to the increase in price and demand for ivory, the authors add that: 

The persistent lack of effective governance in Central Africa and a proliferation of unprotected roads that provide access to hunters combine to facilitate illegal ivory poaching, transport and trade. Forest elephant population and range will continue to decline unless conditions change dramatically.

Habitat loss, often to oil palm plantations for biofuel production, further exacerbates the problem, they write.

Given this dire situation, the authors call for the IUCN to add the African forest elephant onto their species Red List as Critically Endangered (the IUCN currently lists forest elephants as a subspecies of savannah elephants). This upgrade would draw international attention to the problem, the authors hope, which may help boost efforts and support to curb poaching. But reducing demand for ivory, the authors remind, remains the best way to ensure the survival of forest elephants and the countless other species impacted by the illegal wildlife trade.

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A feral cat, just trying to get by. Photo: Topsynette

There are so many ways for a little bird or squirrel to die these days–they can be squished by cars, splattered into buildings, run over by bulldozers, poisoned or even shot. But if you have ever had to clean up a mangled “present” left on your doorstep by a kitty, you’ll know that little creatures can also be killed by pets.

Cats in particular have earned a nasty reputation for themselves as blood thirsty killers of wildlife. They have been named among the top 100 worst invasive species (PDF) in the world. Cats have also earned credit for countless island extinctions. Arriving onto the virgin specks of land alongside sailors, the naive native fauna didn’t stand a chance against these clever, efficient killers. All said, cats claim 14 percent of modern bird, amphibian and mammal island extinctions. But what about the mainland?

A recent study aimed to find out just that. Now the stats are in, and it’s much worse than we thought. But before bird lovers rush to declaw pets, the study’s scientists also found that feral cats and strays–not house cats–are responsible for the majority of the killings.

To arrive at the new findings, researchers from the Smithsonian’s Migratory Bird Center and the U.S. Fish and Wildlife Center assembled a systematic review of every U.S.-based cat predation study known in the scientific literature (excluding Hawaii and Alaska). Based on figures the authors verified as scientifically rigorous, they statistically quantified the total bird and small mammal mortality estimate caused by cats, further breaking the categories down into domestic versus unowned cats, that latter of which the authors define as barnyard kitties, strays that receive food from kind humans and cats that are completely wild. 

Their results paint a grim picture for wildlife. In a paper published today in Nature Communications, they write that between 1.4 to 3.7 billion birds lose their lives to cats each year in the United States. Around 33 percent of the birds killed are non-native species (read: unwelcome). Even more startlingly, between 6.9 to 20.7 billion small mammals succumb to the predators. In urban areas, most of the mammals were pesky rats and mice, though rabbit, squirrel, shrew and vole carcasses turned up in rural and suburban locations.  Just under 70 percent of those deaths, the authors calculate, occur at the paws of unowned cats, a number about three times the amount domesticated kitties slay.

Cats may also be impacting reptile and amphibian populations, although calculating those figures remains difficult due to a lack of studies. Based upon data taken from Europe, Australia and New Zealand and extrapolated to fit the United States, the authors think that between 258 to 822 million reptiles and 95 to 299 million amphibians may die by cat each year nationwide, although additional research would be needed to verify those extrapolations.

These estimates, especially for birds, far exceed any previous figures for cat killings, they write, and also exceed all other direct sources of anthropogenic bird deaths, such as cars, buildings and communication towers.

The authors conclude:

The magnitude of wildlife mortality caused by cats that we report here far exceeds all prior estimates. Available evidence suggests that mortality from cat predation is likely to be substantial in all parts of the world where free-ranging cats occur. 

Our estimates should alert policy makers and the general public about the large magnitude of wildlife mortality caused by free-ranging cats.

Although our results suggest that owned cats have relatively less impact than un-owned cats, owned cats still cause substantial wildlife mortality; simple solutions to reduce mortality caused by pets, such as limiting or preventing outdoor access, should be pursued.

The authors write that trap-neuter/spay-return programs–or those in which feral cats are caught, “fixed,” and released back into the wild unharmed–are undertaken throughout North American and are carried out largely without consideration towards to native animals and without widespread public knowledge. While cat lovers claim that these methods reduce wildlife mortality by humanely limiting the growth of feral colonies, the authors point out that the scientific literature does not support this assumption. Therefore, such colonies should be a “wildlife management priority,” they write. They don’t come out and say it but the implication is that feral cat colonies should be exterminated.

But feral cats, some animal rights advocates argue, are simply trying to eke out a living in a tough, unloving world. As the Humane Society explains, simply removing the cats may not be the most efficient means of solving the problem because cats that are inevitably left behind repopulate the colony, surrounding colonies may move in to replace the old and “the ongoing abandonment of unaltered pet cats…can also repopulate a vacated territory.” Feral cats, after all, are the “offspring of lost or abandoned pet cats or other feral cats who are not spayed or neutered.” Targeting irresponsible humans may provide a different solution, although spay/neuter laws are controversial. 

In Washington D.C. alone, for example, there are more than 300 known feral cat colonies. Wildlife are victims of this problem, but feral cats are too as conditions for survival are tough. And as with so many other environmental banes, the root of the problem neatly traces back to a single source: humans. As the authors write in their paper, feral cats are the single greatest source of anthropogenic (human-driven) mortality for U.S. birds and mammals.

Incidentally, the Humane Society will host World Spay Day on February 26. Find an event for your furry friend to attend, or even host a spaying party yourself. 

Each year, around 5,300 Golden Warblers – a threatened species – die from collisions with communication towers. Photo: Brian Small

Beneath massive communication towers, fallen bird bodies pile up like confetti. They collide with the steel structures—which can reach heights twice that of the Empire State Building—or fly into the miles of cables radiating around the beacons. Each year, nearly 7 million birds lose their lives to these web-like traps of wire and metal—27 times more birds than were killed in the infamous 1989 Exxon Valdez spill.

The killing season peaks during the time nocturnal migratory birds make their way between Canada and the U.S. Flying in the darkness, they spot the tower lights, become disoriented and begin circling the beams. After a storm, when natural navigational cues like the stars or moon are obscured, mortalities are particularly high.

While the magnitude of causalities is worrying, until now researchers did not know whether or not the avian victims were species of conservation concern or just common sparrows. Research recently published in the journal Biological Conservation, however, confirms scientists’ fears. Members of thirteen threatened North American species succumb each year to the towers. The fallen birds represent between 1 and 9 percent of those species’ total population numbers.

“Certain species of birds, including many already in decline, are killed at communication towers in far greater proportions than their abundance would suggest,” said lead author Travis Longcore, the science director of the Urban Wildlands Group and an associate professor of research at the Spatial Science Institute at the University of Southern California, in an email. “And it’s not just these thirteen species we have to worry about—they’re just the ones being killed at the highest rates,” he continued. “Many more species of concern are killed at lower rates, too.”

To figure out mortality by species and regions, Longcore and his co-authors constructed a database of species deaths based on verifiable, available records. Then, they calculated the mean proportion of each species killed and compared those statistics with overall mortality rates for each species’ total population in the U.S. and Canada.

All in all, they found, 97 percent of the birds being killed are passerines, or songbirds. Among the threatened birds that are dying are the Yellow Rail, with 2,200 annuals mortalities, representing 8.9 percent of the species’ total population; the Golden-winged Warbler, with 5,300 annual deaths, representing 2.5 percent of the population; and the Swainson’s Warbler, with 7,500 annual deaths, representing 8.9 percent of the population. Other species, though not currently of conservation concern, still suffer formidable losses. Red-eyed Vireos, for example, relinquish 581,000 lives to communication towers each year, and around 499,000 Ovenbirds die this way, too.

Last year, the same team found that around 1,000 of the towers, used for television and radio broadcast, are responsible for 70 percent of the bird deaths. Those 1,000 towers, the team noted, stand 900 feet or higher, representing the largest of North America’s 70,000-odd communication towers included in the original study. In their follow up study, they identified the deadliest sites, which are in Texas, Louisiana, Florida and the Midwest. The findings are no surprise; the Southeastern coastal plain and the Midwest regions contain the highest concentrations of the tallest towers on the continent.

The Migratory Bird Treaty Act of 1918 makes it illegal to kill migratory birds in the U.S., so the researchers hope their findings may be used to better regulate communication towers. Eliminating the steady-glow red lights from the towers and replacing them with blinking lights—the same fix adopted by the Federal Aviation Administration—may reduce bird mortality by 50 to 70 percent.

The study also carries another lesson, Longcore said. Simply counting up the total number of birds killed by wind turbines, cats, windows, pesticides or communication towers across the country and then making crude comparisons between mortality sources can be misleading, he pointed out. The most impactful data—the types of species killed, and where, and when and how—often lurk beneath those surface figures. “Simple estimates of total ‘bird’ mortality are insufficient; it matters which species are being killed,” he said. “Each mortality source may be significant, but for different species and in different places.”

The crested ibis is one of the world’s most endangered bird species, but captive breeding programs might help it make a comeback. Image via Flickr user Andy_Li

In our October issue, Michelle Nijhuis joins wildlife biologists in searching Colorado’s caves and waterfalls for one of the world’s most mysterious bird species: the black swift. Although fewer than 100 breeding sites of the black swift are known, Nijhuis was lucky enough to see ornithologist Ron Torretta locate a black swift that had been geotagged in 2010, providing researchers with a cache of information about the wanderings of the enigmatic bird. Here are a few more of the most mysterious and elusive of the world’s bird species.

1. Night Parrot: Between 1912 and 1979, birders spotted this elusive species, native to the interior of Australia, exactly zero times—leading most scientists to believe it had gone extinct. Since then, a tiny handful of sightings of the nocturnal, yellow-green bird have occurred, and experts now estimate that the population is somewhere between 50 and 250 mature individuals. After the last verified sighting in November 2006, when park rangers in the state of Queensland turned up a decapitated specimen that had died after flying into a barbed-wire fence, the Australian government chose to keep the find temporarily secret while they searched for more night parrots, so as to avoid an influx of birders flooding the remote park in hopes of spotting one of the world’s rarest birds.

The Ribbon-tailed Astrapia has tail plumage three times its body length, the longest for any bird. Image via Wikimedia Commons/Marka Harper

2. Ribbon-tailed Astrapia: Endemic to the forest highlands of Papua New Guinea, this bird has the longest tail feathers (in relation to body size) of any bird species, with feathers three times its body length. Unfortunately, this stunning plumage has enticed poachers; hunting, along with habitat loss, has led to the species being listed as “near threatened” by the International Union for Conservation of Nature. The species, the most recent bird of paradise to be documented, was first described by explorer Fred Shaw Mayer in 1938.

3. Palila: This species of Hawaiian honeycreeper has one particularly mysterious characteristic—it subsists almost exclusively on the seeds of the māmane plant, which contain a level of toxins that would kill any other small animal. Scientists aren’t sure how the birds digest the seemingly-lethal seeds, although the palila have been observed avoiding certain plants, indicating they might have a way of selecting seeds with lower levels of poison. In 1978, the federal government ruled that feral goats and sheep had to be removed from the palila’s only remaining habitat—the upper slopes of Mauna Kea on the Big Island of Hawai’i—since they consumed māmane plants and threatened the birds’ survival.

The flightless kakapo nearly went extinct when invasive predators were intentionally introduced to New Zealand. Image via Wikimedia Commons/Brent Barrett

4. The Kakapo: Some 82 million years ago, the island of New Zealand broke off from what would become Australia, and the strange, flightless nocturnal parrot species called the kakapo began its unusual evolutionary path. In the absence of predators, it became the world’s largest type of parrot and lost the ability to fly; when European colonists introduced cats, rats and ferrets to New Zealand to control the population of rabbits, the kakapo was nearly wiped out. Now, just 126 wild kakapos live on three predator-free islands off the coast of New Zealand.

5. The Crested Ibis: Named for the crest of white plumage that extends from its nape, the crested ibis used to nest across Japan, China, Korea, Taiwan and Russia. By 1981, after years of habitat loss, just five individuals remained in the wild in Japan, and though scientists took the birds into captivity, a breeding program was unsuccessful. Now, the last remaining wild population—some 500 birds in the Chinese province of Shaanxi—is being buttressed by chicks hatched in captivity as part of a Chinese program. Although the species is still listed as endangered, scientists are cautiously optimistic that it is finally making a comeback.

Snow leopards live in the remote mountains of countries such as Bhutan, China, India, Mongolia and Nepal. They are endangered—a mere 4,000 to 6,000 individuals are spread out over Central Asia—and live solitary lives, usually active just at dawn and dusk. Coupled with their exceptional camouflage, this makes them notoriously elusive—although they figure largely in the mythology of many Asian cultures, wild snow leopards weren’t even caught on camera until the 1970s.

Now, for the first time, a team of researchers from the Snow Leopard Trust and Panthera, a wild cat conservation organization, have captured video of a wild snow leopard mother and cubs in a den, seen above. “This is incredible. Snow leopards are so rare and elusive that people often talk about them as ‘ghosts’ of the mountains,” said Brad Rutherford, Executive Director of the Snow Leopard Trust. “This is the first documented visit of a den site with cubs, and thanks to this video we can share it with the world.”

The search began back in 2008, when an team of scientists affixed GPS collars to several snow leopards encountered in Mongolia’s Gobi Desert. Then, this past May, a pair of females from the study began restricting their movements to a smaller area, indicating they were preparing to give birth. Researchers tracked the VHF signals emitted by the collars through steep mountain outcroppings, coming upon a pair of dens located less than four miles apart in the Tost Mountains on June 21st.

One of the snow leopard cubs discovered in Mongolia’s Tost Mountains. Photo via Panthera/Snow Leopard Trust

“As we stood outside the den we could hear the cub and smell the cats but not see anything inside the den,” said Panthera scientist Orjan Johansson. He and colleagues acted quickly, taping a camera to their antenna pole and extending it over the ledge blocking the den entrance. The footage captured shows a female leopard looking up at the camera, keeping a protective paw over her cub.

At the second den—a narrow crack in a cliff wall—the scientists discovered that the mother was away hunting, leaving her two male cubs unattended, seen below. “This was an unprecedented opportunity,” said Rutherford. “We wanted to be as careful as possible and only take the most pressing data.” The team quickly weighed, measured, photographed and collected hair samples from the cubs, which allowed genetic testing that confirmed sex and other information. More pictures of the cubs are available at Panthera’s photo gallery.

The team also implanted microchip ID tags—each of which are roughly the size of a grain of rice—under the cubs’ skin, which will allow the researchers to identify the animals as part of future conservation projects. After leaving, they tracked signals from the mother’s VHF collar to ensure that she returned to the den, and they note that she is still with the cubs now. The researchers do not plan to visit the dens again, so as to limit future disturbance to the cubs.

The team says that the information collected will be extremely valuable in future attempts to conserve the endangered species. Remarkably little is known about snow leopard behavior, and most of what we understand about the rearing of cubs is known from studying the animals in a zoo environment. Until know, scientists had to speculate about typical litter sizes, cub weights, sex ratios and survival rates.

“Knowledge about the first days and weeks of life is vital to our understanding of how big cat populations work, and how likely it is for a newborn to reach adulthood and contribute to a healthy population,” said Panthera’s Howard Quigley. “A valid conservation program requires such information, which this new development in snow leopard research provides.”

The organization plans to use the microchip ID tags affixed to the cubs to learn about the characteristics of a typical snow leopard upbringing, such as how long the cubs remain in dens, when they being to hunt with their mothers and when they start to venture out on their own. Along with future GPS collaring programs, these data will assist with large-scale conservation efforts across the species’ range.

“We have spent years trying to determine when and where snow leopards give birth, the size of their litters and the chances a cub has of surviving into adulthood,” said Tom McCarthy, director of Panthera’s snow leopard program. “This is one of those exceptional moments in conservation where after years of effort, we get a rare glimpse into the life of an animal that needs our help in surviving in today’s world.”

A hibernating bat stricken with white nose syndrome. Photo via U.S. Fish & Wildlife Service

If you head outside to enjoy a pleasant evening this summer and look carefully, you might notice something subtle missing from the darkening sky: bats. Since 2006, bat populations across the Northeast U.S. have been declining due to the spread of the poorly-understood disease known as white-nose syndrome. The fungal disease, which attacks bats during hibernation and has caused up to 95 percent of particular colonies to die off, has experts concerned that several bat species are headed towards extinction. In 2008, bat expert Alan Hicks said “Most bat researchers would agree that this is the gravest threat to bats they have ever seen.”

Now, according to a study published earlier this week in the journal Ecology Letters, we finally have a better understanding of what makes some species more vulnerable to white nose syndrome than other—and how we can act most efficiently to save them. A team of biologists from the University of California, Santa Cruz examined bat population data collected over the past three decades to determine which of six species have suffered the most from the disease. Their findings indicate that bat species that hibernate in the largest, most social groups tend to die off more quickly and may be on the road to extinction.

A microscopic view of a bat hair colonized by Geomyces destructans, the fungus responsible for white-nose syndrome

“We found that in the highly social species that prefer to hibernate in large, tightly packed groups, the declines were equally severe in colonies that varied from 50 bats to 200,000 bats,” said co-author Marm Kilpatrick in a press release. “That suggests that colonies of those species will continue to decline even when they reach small population sizes.”

The scientists speculate that the close proximity of hibernating bats allows the disease to be transmitted more easily. The fungus, which grows on the bats’ skin during the winter hibernation period, causes a loss of fat reserves, damage to the wing membranes and unusual behavior, even leading some hibernating bats to try flying during the winter. The combination of these symptoms leads to increased bat mortality, which can trigger disruptions throughout local ecosystems—including some we (unfortunately) feel firsthand, like higher amounts of mosquitoes and other insects that bats prey on.

The study also revealed a few pieces of good news, though. Bats that typically hibernate alone (such as the Eastern pipistrelle) experienced much more gradual declines in population than the gregarious species. After several years of declines in the populations of these more solitary bats, their population numbers generally leveled off, reducing the odds of extinction.

Moreover, one particular bat species–Myotis lucifugus, or the little brown bat, the most common species in the Northeast—bucked expectations by actually changing its behavior to ensure a greater survival rate. Although in the past, the species generally preferred to hibernate in clusters and has suffered a major population collapse since the onset of the disease, the researchers now observe roughly 75 percent of individuals roosting solo, which has reduced transmission rates significantly. ”Our analysis suggests that the little brown bats are probably not going to go extinct because they are changing their social behavior in a way that will result in their persisting at smaller populations,” Kilpatrick said.

The study also looked at the variance in disease rates among microclimates within caves, and found that bats hibernating in cooler and drier sites were less likely to be stricken by the fungus. The researchers are unsure why these locations may serve as refuges from the disease and note that more research into transmission is necessary.

The new findings could go a long way in helping us actively conserve bat populations to avoid extinctions. ”Managing disease outbreaks appears to be a daunting task, given the complexity of most ecosystems,” said Sam Scheiner of the National Science Foundation, which funded the study. “This study, however, shows that in fact we can identify the key factors needed for adequate management.”

Some evidence suggests that the fungus can be carried on the clothing of humans entering caves, and in some locations, disinfecting clothes is now required, while other caves have been closed entirely. As a result of the study, immediate conservation efforts can be focused on the species that face the greatest danger.

Flying foxes roost in the trees in Sydney's Royal Botanic Gardens in 2008. (Photo by Sarah Zielinski)

In downtown Sydney, just behind the iconic Opera House, lies the Royal Botanic Garden, 75 acres of flowers, trees and grassy areas first established in 1816 on the site of Australia’s first farm, Farm Cove. The gardens are a place for tourists and the people of Sydney to explore and enjoy, and they’re also a site for conservation research. Because this is one of the biggest green spaces in the city, the gardens are home to plenty of wildlife, including flocks of cockatoos and bats with wingspans a yard wide.

While the cockatoos can be annoying (especially if you’re stupid enough to feed them), the bats—called grey-headed flying foxes—have become a real problem, at least in the eyes of garden management. These mammals are herbivores and leave the human visitors largely alone (though they can at times be incredibly creepy). However, they damage the garden because they defoliate trees. In the more than 20 years since the bats took up residence in the gardens, they’ve killed 28 mature trees, 30 palms and many other plants and damaged another 300. Most worrisome, they settled in the Palm Grove, site of many of the oldest trees in the garden, including historic, exotic species collected from places such as Malaysia and New Guinea. So several years ago the management of the garden decided that the flying foxes had to go.

But grey-headed flying foxes are a species on the decline (IUCN lists them as vulnerable) and protected in Australia. They’ve lost foraging and roosting habitat in many places, and commercial fruit tree growers consider them a pest and kill them (either illegally or with permission from the government).

The Botanic Garden couldn’t kill the bats, though, so they came up with a plan to force them out. They would play recorded noise in late autumn and early winter just before dawn—making it difficult for them to sleep peacefully after a night of foraging—and around sunset, giving them an early wake-up call. The idea is that the bats would be so annoyed that they would decide to roost somewhere else. Wouldn’t you leave a hotel if the people in the neighboring room played loud music when you were trying to fall asleep and you kept getting 3 a.m. wake-up calls?

After several reviews and many delays, the Botanic Garden finally implemented its plan this month. By last week, there were only about 10 bats left in the gardens. The rest appear to have fled a couple of miles south to Centennial Park. The Botanic Gardens will now turn its efforts to restoring the areas damaged by the flying foxes.

The story may not end there, however. The recorded noises will be played only until sometime in July. After that, it would be too disturbing for pregnant flying foxes, who could abort due to the stress, or for new mothers who might be separated from their babies. But flying foxes move seasonally, and come September or October, bats from outside the area could decide the gardens look like a great home.

Garden management is hopeful that the plan will work. After all, the Royal Botanic Gardens Melbourne successfully removed their own grey-headed flying fox population in 2003 using similar methods. Those bats can now be found in nearby Yarra Bend Park.

But was the removal of the flying foxes from the Sydney gardens really necessary? When I first heard of this plan, shortly before my latest trip to Sydney in March, I was sad to hear that the bats would soon be gone. They were one of my favorite memories from my first trip there—looking up on a beautiful fall day to see hundreds of these little Draculas hanging above me. While I was in Sydney this year, I met with Tim Cary, a bat researcher at Macquarie University. He made a good case for why stressing out these animals was akin to torture and contended that the plan was doomed to fail. (Cary suggested tenting the Palm Grove with netting to keep the bats out.)

I also met with Mark Salvio, director of the Royal Botanic Garden, and we spoke at length about the level of destruction, the plans to get rid of the flying foxes and the levels of review and restructuring that the plans had gone through over the years. This isn’t something that is being done without any consideration for the consequences to the grey-headed flying fox species. And as much as I enjoyed the bats during my visits, I could understand that the Garden had placed its foliage as a higher priority–that’s why it exists, to preserve the gardens and their history. (After all, I doubt that the Smithsonian Institution would let its collections be destroyed by, say, insects in the warehouse, even if those insects were an endangered species.)

Did Sydney’s Royal Botanic Garden make the right choice? Is stressing the bats a truly horrible thing to do? Will it even work? We’ll have to wait and see on that last question. As for the other two, I know where Cary stands. Where do you?

Wildlife corridors allow animals to safely cross urban areas. Image by Flickr user Milkwooders

When human urban habitat runs into the terrain of other species, the results can be traumatic for many of the parties involved.

Take coastal southern California, which has seen a big population boom in the past couple of decades. As people built skyscrapers and condos and highways to accommodate their growing numbers, they inadvertently split up the natural habitats of lizards and birds, bobcats and coyotes, and loads of other species. Isolated to much smaller patches of habitat (not to mention surrounded by metal, concrete and plastic), the animals wind up with a much smaller gene pool, making them more susceptible to disease, climate change and natural disaster.

Since the 1960s, a solution often trumpeted by conservationists is to build a “wildlife corridor”: a green pathway that connects one patch of habitat to another, allowing species to move across wider areas despite human developments. These corridors exist or are being built all over the world, from jaguar habitat in the Americas to hardwood forests in Bhutan to tropical rainforests in Australia.

But two active corridor builders are now questioning whether the approach is a good one.

In a commentary published last month in PLoS Biology, conservationists Paul Beier and Andrew Gregory from Northern Arizona University pointed out that there’s actually scant evidence that wildlife corridors work in large, human-dominated landscapes. Almost all research has been done on corridors less than 150 meters long, whereas most implemented corridors are many times larger. What’s more, these studies generally measure only whether animals move from patch A to patch B, rather than explicitly testing genetic diversity or long-term occupancy.

Hoping for better data, the duo has launched a crowd-sourcing project of sorts to identify corridor-like landscapes that would be useful for research. Ideally, they’d like to find spots that meet eight criteria, such as being at least 500 meters long, near urban or industrial activity and stable for at least 20 years after human development. So far, they’re learned of 15 promising sites, but hope to find at least 100. If you can think of one, let them know.

It only took five tries, but his version of Hamlet is much better. Image courtesy of Library of Congress.

You’ve probably laughed at a commercial or television show featuring a chimpanzee dressed like a little kid. They’re cute animals, so how could you resist? But a new study in PLoS ONE provides startling evidence that turning chimps into entertainers makes us care less about them as a species.

Researchers at Duke University had human participants watch a series of television ads (for products like tooth paste and soda) in which they included either a commercial for chimp conservation featuring Jane Goodall, a bit of footage of chimpanzees in the wild or a commercial that had a chimp dressed like a human. The participants were then given a questionnaire that asked about the suitability of chimps as pets, their presence in the media and their status in the wild. They were also asked if they would like to purchase a soda or a tube of toothpaste or to donate to the Red Cross or a conservation organization.

People who saw the chimps dressed as humans were more likely to view the animals as being suitable as pets or in entertainment and were the least likely to donate to the conservation organization. The researchers write:

Advertisers only use easily manageable young chimpanzees in commercials but based on our survey viewers believe these chimpanzees were adults—leaving them unaware of how dangerous these animals can be when fully grown. Such a frivolous use of chimpanzees also leads those watching chimpanzee commercials to overestimate their population size in the wild. Clearly, chimpanzee commercials violated participants’ expectations about how perilously endangered animals are treated. This confusion likely explains why those watching commercials including entertainment chimpanzees donated the least of their experimental earnings to a conservation charity.

“Nobody has measured this sort of thing before, but [our study] clearly shows that the portrayal of endangered species on television can alter viewers’ behaviors and decrease one’s willingness to donate,” says graduate student Kara Schroepfer, the study’s lead author. “This is a clear indication that we need to reevaluate media practices and conservation priorities.”

And the impact of using chimps as entertainers goes beyond the money issue. If people think that chimps make good pets—which is seriously misguided—then more young chimpanzees may be captured in the wild, their mothers killed, so they can be sold into the pet trade. And there is a sad history of chimps being abandoned or killed when they get too old and too dangerous to be cute.

One of Amani's five cubs at seven weeks age (Photo by: Mehgan Murphy, Smithsonian's National Zoo)

If you’ve been paying attention to the goings-on at the Smithsonian Institution, you probably noticed the baby boom at the National Zoo. And one of the biggest success stories is that of the cheetah Amani, who gave birth to five cubs on May 28.

But the rest of her species isn’t doing so well. The wild cheetah population numbers only about 7,500 to 10,000 individuals (an 85 percent decline since 1900) and the captive population has had a tough time having babies. Amani’s litter will be the only captive-born cheetah litter from any North American zoo this year, and 80 percent of captive cheetahs die without producing any offspring.

Scientists are hopeful that may change, though. A new study, published in the Biology of Reproduction and led by researchers at the Smithsonian Conservation Biology Institute, examined the eggs, hormones and uteruses of 34 captive female cheetahs. They found that once the cheetahs had reached about eight years of age, they still produced normal eggs but there were problems with their uterine tracks that would prevent pregnancy.

“We were relieved to find that, unlike in other older mammals, the eggs in older cheetahs can produce viable-appearing and growing embryos, which means we may be able to transfer them to younger cheetahs and preserve genetic diversity,” says the study’s lead author, Adrienne Crosier of the SCBI. Preserving genetic diversity is a prime concern of any breeding program, because inbreeding can contribute to higher numbers of deaths among young offspring as well as lower disease resistance.

SCBI scientists may try an embryo transfer within two years, Crosier says. And other scientists are already thinking about how to use this research to include eggs from wild cheetahs in the captive breeding program.

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Natural History Museum employees are reminded to turn off the lights with a simple sticker

In 2009, the Smithsonian Institution replaced some 15,000 outdated lighting ballasts (devices that turn on fluorescent lights) in the National Museum of American History and the National Museum of Natural History in an effort to improve energy conservation. Of course, all the energy-efficient lighting ballasts in the world won’t make much difference if people keep the lights on all the time.

That’s why Eric Hollinger—an archaeologist with the National Museum of Natural History and co-chair of the museum’s Greening Task Force—devised a simple, low-tech way to remind Smithsonian staffers to flip the switch.

It’s a decal, illustrated in the Smithsonian’s trademark blue and gold, reminding people to turn off the lights when they leave. It’s placed—no surprise—near the light switches in the museum and museum offices. Is it simple? Yes. A bit silly, even? Maybe. But the Smithsonian’s greening experts have high hopes that, used in conjunction with energy-efficient lights, these decals could markedly augment energy savings throughout the institution.

After using 28,072,619 kilowatt hours of electricity at a cost of nearly $3.5 million in 2009, Hollinger’s greening task force began discussions with staff members regarding opportunities for conservation and sustainability within the museum. One recurring topic of conversation was the frequency with which staff members left the lights in their offices and hallways on when, well, nobody was home. “A lot of staff felt that people just weren’t as cognizant of it because they didn’t see the electricity bills. There wasn’t that personal connection to it,” said Hollinger.

Stickers such as those Hollinger has developed were ubiquitous in the museum during the years of the Carter administration, but due to renovations, repairs and repainted walls, they have since disappeared. So, Hollinger decided to start investigating the conservation potential in resurrecting the old stickers.

“People were saying, ‘well, it’s not worth it if I’m only leaving my office for 20 minutes,’” Hollinger said. “They were rationalizing not turning the lights off.” This laid the foundation with two preliminary points of research: first, learning exactly how much energy is spent by turning the museum’s lights on, which requires an initial surge of energy supplied by the ballasts. And second, calculating how much time lights would have to be turned off in order to make up the difference.

Hollinger discovered that thanks to the new energy-efficient lighting ballasts, turning off the lights for 5 minutes or more was more efficient than leaving them on. He also found a Canadian study in which decals similar to those he envisioned had been put up in an office space and had more than paid for themselves in energy savings within less than two months. Hollinger then started looking into the cost-efficiency of printing stickers for the museum. Enlisting the help of Chief of Exhibit Design Michael Lawrence at the National Museum of Natural History to create the design, Hollinger and Lawrence developed a sticker that would cost 12 cents apiece. According to Hollinger’s calculations, if used throughout the entire museum, the $700 investment would pay for itself in as little as two and a half weeks and would result in a 15 to 20 percent decrease in energy used in office spaces. With the endorsement of museum director Christian Samper, the stickers have been purchased and are being mounted.

While there has been a sharp dip in the electric bill since replacing the ballasts, it is difficult to tell how much energy has actually been saved due to the decals rather than the new, energy-efficient ballasts. But Nancy Bechtol, Director of the Office of Facilities Management and Reliability, thinks Hollinger is onto something; she has purchased the decals for the entire Smithsonian Institution. “I asked Eric, ‘Do you mind if we buy 25,000 of these?’” Bechtol recalled. Once the decals are put up throughout the Smithsonian museums and offices (some of which have older, less efficient ballasts), it should be possible to tell whether or not they make a difference.

In 2009, the Smithsonian Institution won a sustainability award from the U.S. General Services Administration for an energy-efficient chiller plant (a large, water-based cooling system) that provides air conditioning at a lower environmental impact (and cost) to the National Museum of American History. Part of a larger effort to increase energy savings throughout the Smithsonian, the project also included a hot water system upgrade and revamp of the chiller plant and ventilation systems at the Natural History Museum, in addition to replacing the lighting ballasts.

But while these large-scale initiatives may contribute substantially to sustainability in the Smithsonian, simple things can contribute to energy conservation—like turning off the lights.

Mangrove forest, courtesy of Flickr user peyri

There’s nothing that conservationists would like better than proving that protecting nature is good for people too, which is one reason why I try to remain skeptical about such claims. After all, when you fence in forests and wildlife, you’re eliminating an important source of income, food and land for locals. In addition, protected areas are often located in the most impoverished areas, where communities have little chance of opposing pressure for conservation.

But a study published this week in Proceedings of the National Academy of Sciences provides some powerful new evidence that protected areas in Costa Rica and Thailand have boosted livelihoods. Although people near protected areas are still less well-off than the rest of the country, researchers found this had more to do with confounding variables such as forest cover, land productivity and access to transportation, which influenced both the placement of parks and the livelihood of residents. After removing those effects, the researchers found that the presence of parks reduced poverty in Costa Rica and Thailand by 10 percent and 30 percent, respectively.

The new study isn’t the only evidence that conservation is good for the economy. In the current issue of Nature Conservancy magazine, I examined the value of mangrove forests to local communities. Off the Gulf of California in Mexico, for instance, fishermen living near the biggest mangroves reel in the most fish and crab. Specifically, each acre of mangrove brought in about $15,000 per year in seafood, a dollar amount 200 times higher than the forest’s timber value.

Mangroves also save lives. Their spidery roots can reduce the force of waves pummeling the land during severe storms. Saudamini Das, an economist with India’s Institute of Economic Growth, estimates that mangroves saved nearly 20,000 lives during the 1999 Orissa Cyclone in the Indian Ocean.

On the other hand, not every ecosystem will have as many tangible benefits as mangroves, and not every country can be Costa Rica, which has set aside a quarter of its land for conservation. As the Nature Conservancy’s chief scientist, Peter Kareiva, puts it, “Quantifying ecosystem services will not protect all of the nature you want to protect, but it will generate public support for an awful lot of conservation.”

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.