Monday 16 December 2019

Savannah monitor lizards have a unique airflow pattern that is a hybrid of bird and mammal flow patterns

DECEMBER 14, 2019


Take a deep breath in. Slowly let it out.

You have just participated in one of the most profound evolutionary revolutions on Earth—breathing air on land. It's unclear how the first vertebrates thrived after crawling out of the sea nearly 400 million years ago, but the lungs hold an important clue.

Birds, reptiles, mammals and birds have evolved diverse lung structures through which air flows in complicated ways. Birds and mammals are on extreme ends of the airflow spectrum. Mammals inhale oxygen-rich air that funnels into smaller branches, ending in tiny sacs where oxygen enters and carbon dioxide leaves the bloodstream. When mammals exhale, the depleted air follows the same route out of the body, exhibiting a so-called tidal flow pattern.

In contrast, bird breath travels tidally through part of the respiratory system, but in a one-way loop throughout most of the lung. Thanks to a unique design with aerodynamic valves, air always moves toward the head through many tiny tubes in birds—during both inhalation and exhalation. Scientists thought this pattern of flow is hyper efficient and evolved to support flight until University of Utah biologist Colleen Farmer's research group discovered that alligators and iguanas also have a unidirectional air flow pattern.

In their latest study, U biologists have discovered that Savannah monitor lizards have lung structures that are a kind of a hybrid system of bird and mammal lungs. The researchers took CT scans of the entire lung labyrinth and used two different supercomputers to simulate airflow patterns at the highest resolution. The software used computational fluid dynamics similar to those used to forecast weather, calculating millions of equations every tenth of a second. The findings show that vertebrate lung evolution is complicated and we have yet to understand the full picture.

Imperiled Yellow-legged Frogs Protected Under California’s Endangered Species Act - via Herp Digest

Press Release, December 11, 2019 
Contact: Jeff Miller 510 499-9185 jmiller@biologicaldiversity.org

SACRAMENTO— The California Fish and Game Commission today approved California Endangered Species Act protections for five of six populations of the foothill yellow-legged frog, a species that has disappeared from more than 50% of its historic habitat in the state. The decision responds to a 2016 petition by the Center for Biological Diversity.

“This is really good news for these iconic but highly imperiled stream-dwelling frogs,” said Jeff Miller, a senior conservation advocate with the Center. “Protecting them will also help safeguard beautiful coastal and Sierra foothill streams which we all rely on for clean drinking water and recreation.”

The commission today unanimously voted to protect Southern Sierra, Central Coast and South Coast populations of the frog as endangered; and the Northern Sierra and Feather River populations as threatened. The California Department of Fish and Wildlife determined that foothill yellow-legged frogs in California’s North Coast do not currently warrant protection.

Foothill yellow-legged frogs were once found in streams and rivers along the lower western slopes of the Sierra Nevada as well as in Pacific Coast drainages from the Oregon border to at least as far south as Los Angeles County. This species has now disappeared from more than half of its former California range.

Foothill yellow-legged frogs are impacted by a wide range of threats, including dams, water diversions, logging, mining, livestock grazing, climate change, pesticides, off-road vehicles, disease, urban and agricultural expansion and marijuana cultivation.

Background

Adult foothill yellow-legged frogs (Rana boylii) are from 1.5 to 3 inches long, with a distinctive lemon-yellow color under their legs. They inhabit partially shaded, rocky perennial streams, and their life cycle is synchronized with the seasonal timing of streamflow conditions. These frogs need perennial water where they can forage through the summer and fall months.

The Northern Sierra population ranges from the Middle Fork American River in El Dorado County, north through the Sierra foothills to the upper Yuba River watershed in Plumas County. The Southern Sierra population ranges from the South Fork American River watershed, south through the Sierra foothills to the Tehachapi Mountains. The genetically unique Feather River population is primarily in Plumas and Butte counties.

At least half the known historical frog populations have been lost in every northern and central Sierra county except Plumas County. Healthy frog populations remain in the northern and central Sierras in the American, Clavey, Cosumnes, Feather, Merced, Mokelumne, Stanislaus, Tuolumne and Yuba rivers.

The Central Coast population lives south of San Francisco Bay in the Coast Ranges to San Benito and Monterey counties. Significant foothill yellow-legged frog populations remain in the Diablo Range. The South Coast population is west of the Salinas Valley in Monterey County and south into the southern Coast Ranges. These frogs have now disappeared from all coastal streams south of San Luis Obispo County.

The Center petitioned in 2012 to protect the foothill yellow-legged frog under the federal Endangered Species Act. Under a lawsuit settlement agreement with the Center, the U.S. Fish and Wildlife Service will decide by 2020 on whether the species warrants federal protection.


Friday 13 December 2019

EPA Weakens Safeguards for Weed Killer Atrazine, Linked to Birth Defects - via Herp Digest

The reversal is the Trump administration’s third about-face on a toxic pesticide.

The Trump administration plans to weaken environmental safeguards for atrazine, the second most widely used herbicide in the U.S., even though it’s known to castrate frogs and is linked to birth defects and cancer in humans and animals.

The U.S. Environmental Protection Agency (EPA) announced last week that it would allow 50 percent more atrazine in the surface water along the nation’s waterways, despite the agency’s own assessment, which in 2016 found that the weed killer poses a chronic risk to fish, amphibians, and aquatic invertebrates and suggested that its allowable amount should be significantly decreased.
Atrazine is banned in Europe, due to its potential to contaminate water sources, but widely used in the U.S., where about 70 million pounds of the pesticide is sprayed—mostly on corn, but also on sorghum, sugarcane, and a few other crops, as well as on golf courses, Christmas tree farms, and in residential landscaping. Runoff washes the chemical into streams, rivers, and groundwater; it’s one of the most common pollutants found in American waters.

Independent research has shown atrazine’s impact on aquatic life is significant: it can lead to reduced survival, growth, immunity, and sensory capacities, increased disease, as well as reproductive and developmental abnormalities, and behavioral changes. There’s also evidence the herbicide harms plants and wildlife. In humans, it’s associated with thyroid, ovarian, and other cancers, low birth outcomes, pre-term delivery, and birth defects. In 2016, California added atrazine and related chemicals to the Proposition 65 list, listing them as substances known to cause reproductive and developmental toxicity.

Of major concern is atrazine’s impact on endangered species. The EPA has already found that the chemical’s use will likely adversely affect California Red-legged frog and Delta Smelt, Pallid Sturgeon, two freshwater mussels, the Topeka Shiner, and several other species.

“Atrazine is a hundred times worse than glyphosate, the active ingredient in Roundup, because it’s an endocrine disruptor,” said Nathan Donley, a scientist at the Center for Biological Diversity, which has called for a complete ban of the chemical. “It can have huge impacts and should have been banned a long time ago.”

Atrazine has been mired in controversy since Dr. Tyrone Hayes, an industry funded scientist-turned-whistleblower, published a study showing the chemical alters the sex lives of adult male frogs, emasculating most and turning some into females. The feud between Hayes and Syngenta, the biggest manufacturer of atrazine in the U.S., revealed the industry’s zeal to discredit independent scientists, push its own studies, and hold sway in the government’s regulatory process.

The reversal on atrazine is the Trump Administration’s third about-face on a toxic pesticide.

In July, the EPA announced it would not ban the pesticide chlorpyrifos as previously scheduled, despite numerous studies showing it causes brain damage and impairs children’s IQ scores. The EPA’s own assessment concluded that the levels of chlorpyrifos currently found on food and in drinking water are unsafe and Hawaii and California have already banned the pesticide outright. (In California, it was already banned for household use but is widespread in agriculture.)

That same month, the EPA said it would end long-running safeguards meant to protect children from exposure to pyrethroids, a class of insecticides used in bug sprays, pet shampoos, and on fruits and vegetables. The move will triple the amount of exposure to pyrethroids that’s considered safe for children. The EPA decided to get rid of the child safety standard despite evidence from peer-reviewed studies that pyrethroids can cause learning deficiencies and neurodegenerative effects associated with Alzheimer’s and Parkinson’s diseases, among other impacts.

EPA Says Atrazine is No Longer Extensively Harmful

Atrazine is one of the most studied and monitored pesticides, due to a 2003 agreement between the EPA and Syngenta and other small atrazine manufacturers. If a watershed shows atrazine concentrations above the allowed threshold in any two years of monitoring, Syngenta must do mitigation activities to reduce atrazine exposure, such as education and outreach programs for growers and distributors.

EPA’s plan to lower safeguards for atrazine is part of the chemical’s current registration review, conducted to reapprove its use. In the 2016 EPA review—a preliminary ecological risk assessment of atrazine based on the analysis of newly available science and monitoring data—the agency found extensive environmental harm. But in the memorandum posted last week, the EPA said some studies used in that review are fundamentally flawed and the review ignores recommendations made by previous scientific panels.

As a result, the agency says it plans to change the current Concentration Equivalent Level of Concern (CELOC), a threshold meant to protect aquatic life, from a 60-day average concentration of 10 parts per billion of atrazine to 15 parts per billion. The newly proposed benchmark is almost five times higher than the 3.4 parts per billion that the EPA identified as safe in the 2016 review.

The agency told Civil Eats that the threshold (CELOC) is not used as justification for increasing allowable atrazine levels in waterways. But while the CELOC doesn’t technically raise allowable atrazine levels, by raising its concentration the EPA will allow more atrazine to be in the water before steps are taken to reduce its levels.

And while the threshold is based on the potential for recovery of aquatic communities, scientists say the health of plant communities is generally indicative of that of the entire ecosystem due to cascading effects down the chain.
The EPA also said they changed the CELOC in response to significant public comments about the level of regulation, and the inherent uncertainty related to the data.

“It’s ironic [the EPA] would move to increase the allowable levels after previously coming to the correct conclusion that atrazine is an environmental and biological hazard,”
Hayes told Civil Eats. “Given that research shows that fish and amphibian reproduction and behavior can be damaged by atrazine at levels as low as 0.1 parts per billion (ppb), raising the acceptable levels to 15 ppb is disastrous.” He added that the policy change will certainly harm the already-declining fishing industry.

Syngenta, the agrichemical giant that makes most of the atrazine available on the market, says the chemical is safe at levels found in the environment. “Atrazine’s safety has been established in nearly 7,000 scientific studies over the past 50 years,” Ann Bryan, the company’s senior manager for external communications, said in a written statement provided to Civil Eats.

Industry Intimidation of Scientists

Hundreds of independent lab and field studies have found evidence that opposes Syngenta’s claims. But it was Hayes, a University of California, Berkeley scientist whom Syngenta paid in 1998 to run experiments on atrazine, who fired the first salvo. When he discovered the herbicide altered the sex lives of frogs, the company tried to block the results, Hayes said. And because he refused to toe the company line, the scientist severed ties with Syngenta in 2000. He then repeated the experiments and published a study that showed frogs changed sex by exposure to atrazine at levels 30 times below what the EPA permits in water.

Hayes has since openly fought Syngenta, published other papers, and reported that he had found frogs with sexual abnormalities in atrazine-contaminated sites in Illinois, Iowa, Nebraska, and Wyoming. According to a review by Hayes, the best predictor of whether a study has found atrazine to have significant biological effects was the funding source; when research was funded by the pesticide’s manufacturer, studies have found either no effect or only small effects.

Despite his findings, the EPA approved the continued use of atrazine in 2004. That same year, the European Commission banned the chemical and a class-action lawsuit was filed by several Midwestern cities and towns accusing Syngenta of contaminating their drinking water. The documents unsealed in those lawsuits showed that Syngenta worked to discredit Hayes, with company reps following him to lectures, and attacking him both personally and professionally.

Several other papers also have pointed out flaws in the EPA’s approach to regulating the chemical and the bias embedded in atrazine studies and other publications funded by Syngenta. The researchers in the two studies linked above say the EPA is mired in conflicts of interest and has used only a small portion of the available data to determine a chemical’s impacts, often relying exclusively on industry-supplied studies. In its recent 2012 reassessment of atrazine impacts on amphibians, for example, the EPA relied on a single industry-funded study, while excluding 74 other published studies because they did not meet rigid criteria for study inclusion.

A number of independent studies have detected no or minimal effects of atrazine on amphibians or fish—though reviews suggest some of those studies might be flawed.
Jason Rohr, a professor at the University of Notre Dame and an expert on atrazine’s effects on amphibians, said it’s hard to know how the new allowable levels of atrazine will impact aquatic life. But, he added, it certainly won’t improve the quality of America’s waterways.

“This EPA decision will very likely result in freshwater ecosystems being exposed to both higher concentrations of atrazine and for longer periods of time,” he told Civil Eats. “This is potentially consequential because this chemical is clearly associated with a myriad of adverse effects on freshwater organisms.”

The EPA decision will also impact humans. Drinking water wasn’t mentioned in EPA’s announcement last week since it’s related to an ecological risk assessment, not to a human health risk assessment. But the two issues are related: the decision to allow a higher level of atrazine in surface waterways will impact humans because many of those waterways serve as drinking water sources, said Olga Naidenko, vice president for science investigations with the Environmental Working Group (EWG). This means, she said, that “water utilities would need to expend more resources to lower atrazine levels to the legal standard for drinking water.

Already, atrazine taints the tap water of nearly 30 million Americans in 28 states, according to an analysis published by EWG last year. EPA monitoring data show that seasonal spikes of atrazine in drinking water (which happen when the chemicals are being applied in the fields) are often three to seven times higher than the federal legal limit. But these numbers are not reported to people in the affected communities because the Safe Drinking Water Act allows utilities to report only annual averages.

The EPA decision will likely increase atrazine levels in drinking water, both in wells and municipal sources, said Rohr, because many of the water treatment plants in the Midwest—where atrazine is used heavily—can’t afford to use the expensive activated carbon needed to remove it from drinking water. In 2012, Syngenta agreed to pay $105 million to settle a class-action lawsuit over atrazine-contaminated water supplies after more than 1,000 community water systems filed reimbursement claims for having to filter the chemical from their drinking water.

Donley, from the Center for Biological Diversity, pointed out that EPA’s reversal on atrazine may be linked to the fact that former Syngenta lobbyist Jeff Sands was appointed as a top agricultural advisor to then-EPA administrator Scott Pruitt in 2017. At the time, the White House signed off on an ethics waiver that allowed Sands to work at the agency despite his previous role. (Sands left the EPA in 2018 and there’s no proof that he influenced the atrazine decision.)

Other weakening of pesticide rules may also be in the works, Donley said, as several controversial chemicals are undergoing their periodic registration review, including paraquat, neonicotinoids, and several fumigants. And once the agency publishes final rules, they can only be challenged in court—not an easy thing to do. For this reason, what happens now will likely have an impact on the environment for years to come. As Donley put it: “This administration has a lot of power in dictat[ing] the next 15-20 years for these pesticides.”

We Need to Treat Human Noise as a Global Pollutant, New Study Says - via Herp Digest

ScienceAlert, 11/20/19

It is well known that human hubbub can have a negative impact on some animals, but a new study Wednesday says the noise we make should be treated as a "major global pollutant".

"We found that noise affects many species of amphibians, arthropods, birds, fish, mammals, mollusks and reptilians," scientists at Queen's University Belfast said in the Royal Society's Biology Letters.

Human noise pervades the environment, from vehicles and industry in dense urban centres, to planes flying overhead, to ocean going vessels whose propellors are thought to interfere with whale sonar communications and may be implicated in mass beaching as the disorientated animals lose their sense of direction.

Reviewing a series of individual studies in what is known as a meta-analysis, Hansjoerg Kunc and Rouven Schmidt said the issue should be seen as the "majority of species responding to noise rather than a few species being particularly sensitive to noise.”

"The interesting finding is that the species included range from little insects to large marine mammals such as whales," he Kunc told AFP.

"We did not expect to find a response to noise across all animal species.

The paper said that an animal's response to the clatter of human activity is not necessarily straightforward, and cannot be easily termed as positive or negative.

Human made noise, for example, has been shown to interfere with the sonar detection systems that bats use to find their insect prey, making it more difficult for the flying mammals to catch insects.

But that may be good news for the bugs: "Potential prey may benefit directly from anthropogenic noise," the paper said.

Kunc cautioned, however, that the big picture is still one of serious disruption across the natural environment.
"In the bat example, the predator might suffer because they cannot locate their prey... but in species where potential prey rely on sound to detect predators, the prey might suffer because they might not be able to hear them early enough to escape.”

Human sound pollution and the animal response to it must be seen in the context of an ecosystem, especially when considering conservation efforts, the authors note.
"Noise must be considered as a serious form of environmental change and pollution as it affects both aquatic and terrestrial species," they said.

"Our analyses provide the quantitative evidence necessary for legislative bodies to regulate this environmental stressor more effectively."

Caribou migration linked to climate cycles and insect pests

DECEMBER 12, 2019



Caribou weakened by harassing insects in the summer take longer to migrate to calving grounds the following spring. This means calves have less time to fatten up before winter. As Arctic summers continue to grow warmer and favor more insects, caribou populations could suffer. Credit: NPS/Kyle Joly

Caribou, the North American cousin of reindeer, migrate farther than any terrestrial animal. They can cover thousands of miles as they move between winter feeding grounds and summer calving grounds. But many caribou herds are in decline as the warming climate changes much of the landscape they depend on. Inedible shrubs are rapidly encroaching on the tundra, and more frequent forest fires and disease are destroying the trees that provide caribou with lichen for food. The role of climate on their migration patterns has never been well understood, but knowing what drives caribou movements is crucial to predicting the future for the iconic species that plays a key roll the ecological and economic stability of the Arctic region.

A new study led by a University of Maryland biologist discovered two unexpected drivers for migration timing that dispute long-held assumptions and provide insight into potential future effects of climate change on caribou. First, the study found that caribou herds all across North America are triggered to start spring migration at roughly the same time by large-scale, ocean-driven climate cycles. Second, despite a synchronized start, arrival at their respective calving grounds depends on the previous summer's weather conditions. Warm, windless summers that favored insect pests lead to poorer maternal health and delayed arrivals at the calving grounds the following spring.

The study, which accounted for approximately 80% of all North American migratory caribou, is the largest caribou migration study to date. It was published in the December 12, 2019 issue of the journal Ecosphere.

"This was completely unexpected," said Eliezer Gurarie, an associate research scientist in UMD's Department of Biology and lead author of the study. "There was no reason to think that herds that calve near the Hudson Bay in the East would begin migration at the same time as the herds along coastal Western Alaska, or that summer conditions would play an important role in the following spring migration. Prior to this, it had been assumed that migration timing depends on some combination of snowmelt and availability of useful vegetation at the endpoint of the migration. Neither of those held up."

Northern Ireland's recovering pine marten population benefits red squirrels


DECEMBER 13, 2019


The recovery of pine marten in Ireland and Britain is reversing native red squirrel replacement by invasive grey squirrels, according to new research presented at the British Ecological Society's annual meeting in Belfast today.

Researchers at Queens University, Belfast and National Museums Northern Ireland have found red squirrels are responding positively to the increased presence of pine martens across Northern Ireland. So, where pine martens occur, it increases the chances of red squirrels occurring, simultaneously reducing the likelihood of grey squirrels being present.

Historically, persecution of pine marten and loss of their preferred habitat led to severe declines across Ireland and Britain. In Northern Ireland, small, remnant populations were all that remained, but today, the species is recovering, and this comeback may help ensure the long-term future of the red squirrel in Ireland.

Joshua Twining, who will be presenting the research at the conference, commented "the red squirrels 'positive response' is likely due to grey squirrel disappearance rather than red squirrels and pine martens working together." Pine martens eat both red and grey squirrels, though the key difference is that red squirrels have evolved alongside pine martens over millennia, making them able to coexist.

Twining said, "The ability of the pine marten to control the grey squirrel and help red squirrel recovery in Ireland and Britain is limited by three things; its ongoing recovery, the lack of forest cover on the island and the presence of urban areas. Twining and co-authors suggest that grey squirrels will persist in the latter as results show pine marten are forest specialists and avoid urban areas.

Although the red squirrel population is increasing in Northern Ireland, the researchers warn that "unless the issue of control within populated areas is addressed, we risk creating a situation where marten-savvy grey squirrels could recolonise the wider landscape in the future".

Thursday 12 December 2019

Key to helping southern sea otter is in repopulating estuaries such as San Francisco Bay

DECEMBER 10, 2019


The picture of sea otters frolicking among kelp beds and rocky shoals has become an iconic image of the California coastline. But it may be drawing attention away from the value of other habitat that could truly help the endangered species in its recovery—estuaries.

In fact, a new study released today concludes that California could more than triple its population of southern sea otters, from an estimated 3,000 to nearly 10,000, by repopulating the largest estuary on the coast—the San Francisco Bay.

"It would essentially end up lifting the sea otter out of its endangered species status," said Brent Hughes, assistant professor of biology at Sonoma State and lead researcher in the study published in PeerJ. "For the conservation of the sea otter, this would be huge."

According to Hughes and fellow researchers, current southern sea otter recovery plans have not included estuaries as target habitats. This "may be an artifact of where the surviving population persisted," they concluded in their paper titled "Species recovery and recolonization of past habitats: Lessons for science and conservation from sea otters in estuaries."

"Sea otters are widely associated with kelp forests in the minds of both the scientific community and the general public," said Lisa Needles, a member of the research team based at California Polytechnic State University. "However, over the last two decades, we've seen the resurgence of sea otters in two estuaries, Morro Bay and Elkhorn Slough. This led us to realize that not only did they occur in estuaries in large numbers in the past but they're also integral to the ecosystem health of estuaries, just as they are in kelp forests."

The southern sea otter was widely believed to be extinct due to the expansive fur trade of the 18th and 19th centuries, which reduced the global population from between 150,000 and 300,000 to roughly 2,000. Then in 1914 a remnant population of about 50 southern sea otters was found along the rugged Big Sur shoreline. Thanks to conservation efforts, the population has since grown to more than 3,000, but their numbers are still far below their historic numbers and range.

While conservation efforts have focused on protecting otters in these rocky coastal habitats, evidence shows that southern sea otters were once abundant in California estuaries, including in San Francisco Bay. Early accounts by Spanish explorers noted otter populations as far south as San Jose and as far north as Richardson Bay. "Sea otters probably numbered in the thousands in this estuary prior to being driven to local extinction by over-hunting," the researchers noted.

To save koalas from fire, we need to start putting their genetic material on ice

DECEMBER 10, 2019

by Ryan R. Witt, Chad T. Beranek, John Clulow, John Rodger, Lachlan G. Howell and Robert Scanlon, The Conversation

Thousands of koalas may have died in fires burning through New South Wales but expert evidence to a state parliamentary inquiry on Monday said we are unlikely to ever know the real numbers.

Unprecedented fires have burned through millions of hectares of forest, including koala habitat and rainforests untouched by fire for thousands of years.

The devastation won't stop once the fires are out. Koala populations that survive the fires could be cut off from each other, lowering their genetic diversity and threatening their long-term survival.

To protect Australia's iconic koalas we need to start freezing their genetic material. With more investment in the fast-developing field of cryogenics, koala hospitals could start taking samples from their patients, creating a vital lifeline for the species as a whole.

Koala-threatening fires are getting worse

Fire seasons are starting earlier, lasting longer and becoming more intense, made worse by climate change.

This season, there is an above-average risk of serious fires across an extensive range of koala habitat on Australia's east coast.

Experts at the NSW inquiry estimated about 2,000 koalas may have died in fires already this year, and the destruction of habitat means further population declines are inevitable. With areas not usually threatened by fires now at risk, we need new plans for future conservation.

Boy oh boy! Twin male pandas charm Berlin zoo

DECEMBER 9, 2019

Berlin's Mayor Michael Mueller with "Meng Yuan"

The cuteness level at Berlin Zoo doubled on Monday when a pair of twin panda cubs made their public debut, with the zoo revealing the cuddly bundles of fur were both boys.

The little ones were born at the zoo on August 31 but in keeping with Chinese tradition they were only named after 100 days.

Speaking before a crowd of excited reporters at the Panda Garden, zoo director Andreas Knieriem announced that the cubs would go by the names of Meng Xiang, meaning "long-awaited dream" and Meng Yuan, or "dream come true".

The twins, weighing around six kilos (13 pounds) each, then made their long-awaited first appearance before the world's media.

Wheeled out in a glass-cased "panda bed", they were seen lounging close together on a heated mattress.

One of the cubs appeared half-asleep and unfazed by the attention, while his more active brother repeatedly turned his back on the press pack, prompting coos and laughter.

But the general public will have to wait a little longer for their own glimpse of the zoo's newest stars.

The cubs will be kept away from visitors "until they can walk properly" and are more familiar with their surroundings, Knieriem said, expected to be sometime in early 2020.

Wednesday 11 December 2019

Close friends help macaques survive

DECEMBER 10, 2019

Close friendships improve the survival chances of rhesus macaques, new research shows.

University of Exeter scientists studied the social lives of female macaques on "Monkey Island" (Cayo Santiago, off Puerto Rico).

Data spanning seven years revealed that females with the strongest social connection to a another macaque—measured by factors including time spent together and time grooming each other's fur—were 11% less likely to die in a given year.

"We can't say for certain why close social ties help macaques survive," said lead author Dr. Sam Ellis, of Exeter's Centre for Research in Animal Behaviour.

"Having favoured partners could be beneficial in multiple ways, including more effective cooperation and 'exchange' activities such as grooming and forming coalitions.

"Many species—including humans—use social interactions to cope with challenges in their environment, and a growing number of studies show that well-connected individuals are healthier and safer than those who are isolated."

The study focussed on four measures of social connection:
Associating with many other macaques
Having strong connections to favoured partners
Connecting the broader group (being a link by associating with several sub-groups)
A high rate of cooperative activities such as grooming

Researchers Discover Secret Breeding Ground of World’s Most Endangered Crocodile (Gharials) - via Herp Digest

Over 100 recently-hatched gharials were found deep in Nepal’s Bardia National Park
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by Jason Daly SMITHSONIAN.COM ,11/21/19

Stumbling into a secret crocodile breeding ground is likely more startling than exciting for most people—unless you’re a scientist and those crocs just happen to be one of the world’s most endangered reptiles. That’s what happened to researchers from the Zoological Society London (ZSL) and Biodiversity Conservancy Nepal when they found a group of adult gharial crocodiles, watching over 100 hatchlings deep inside Nepal’s Bardia National Park.

The species, Gavialis gangeticus, has not been recorded breeding in the borders of the park since 1982. Gharial crocodiles are oddball reptiles with bulging eyes and a narrow toothy snout. In adulthood, they can reach 16 feet in length and weigh up to 550 pounds.

But the population has dropped 98 percent since the 1940s, according to a ZSL press release. The crocs are now listed as critically endangered by the IUCN, which administers the global endangered species list, with only 650 to 900 mature individuals left in 14 locations in Nepal, India and Bangladesh. The species has already gone extinct in the nations of Bhutan, Myanmar and Pakistan.

So finding a breeding colony of the animals is a big deal. Ashish Bashyal, conservation scientist with the Biodiversity Conservancy Nepal and co-founder of the Nepal Gharial Conservation Initiative, tells Greg Norman at Gizmodo that despite searching, the team had never found baby gharials in the park—even though it supports an excellent gharial habitat.

“Something that was bugging me was that we had been working there for almost three years, had conducted more than three surveys, but we had never found hatchlings, baby gharials,” he says. “So they are out there, they have good habitat, there are adult males, adult females. So on the surface everything is in place for them to breed and reproduce… but we were not finding any babies.”

During a survey in February, however, the project witnessed gharials showing signs that they might be mating. So the team decided to revisit the area in June, when any resulting offspring would hatch. Getting to the site in the dry season, however, was arduous. Low water levels meant they couldn’t raft down the river, the easiest way to access the site. Heavy rains two days before their scheduled trip also made driving close to the site impossible. So the team trekked a rugged 6.2 miles through the jungle in 104 degree temperatures, encountering fresh tiger tracks along the way.

The slog paid off. They spotted the gharial site from a nearby ridge, observing dozens of little croclings swimming around and basking on a sandbar.

“At around [one foot] in size, they look exactly like miniature versions of adult gharials – so incredibly cute,” Bashyal says in the press release.


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(Zoological Society of London)
The initial find took place in June, though details about the discovery are just being released. ZSL researcher Rikki Gumbs tells Helen Briggs at the BBC that the little reptiles were spotted again recently, after the summer monsoon rains.

“They’ve made it through the first big hurdle,” Gumbs says. “Especially with the threats that are impacting the species, it’s very important that these hatchlings can make it to adulthood.”

But the monsoons are the least of their worries. The reptiles, which once numbered in the tens of thousands, declined after river dams changed and fragmented their habitat throughout South Asia. The animals were frequently hunted for their hides and eggs and also caught in fishing nets. While harming the animals is now illegal, other problems continue to persist. Dam construction, irrigation canals, sand mining and pollution are all still threats to the long-nosed crocs.

Bashyal says that the best protection for the animals is to get local people involved. He hopes to set up “gharial guard groups” to watch out for the animals, similar to groups established in Chitwan National Park, the only other site in Nepal that gharials call home.

“People generally have a great affinity for gharials, they don't attack humans as they generally feed on fish–and their snout is much too fragile,” he says in the release. “We want to try and harness that love for the animal into local community conservation action in order to help monitor how the hatchlings fair.”

Helping the gharial, he tells Norman at Gizmodo, could help many other species that call Nepal’s rivers home. “Ecologically, I always like to emphasize the fact that they are like the tiger of the rivers,” he says. “They are an umbrella species, so if we protect our waterways, protect our gharials then that will benefit other endangered species we have such as the gangetic dolphin and the smooth-coated otter.”

Bardia is not the only spot where the crocodiles are breeding. In August, the National Chambal Sanctuary in India announced that over 5,000 hatchling gharials were born in the river over the summer. However, it will still take lots of monitoring of pollution and poachers to allow even a small percentage of the baby crocs to make it to adulthood.
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