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Madison, WI, United States

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Madison, WI, United States
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News Article | February 3, 2016
Site: news.yahoo.com

Thousands of dead seabirds have washed up on Alaskan shores over the past nine months. And while a dead bird washing ashore is a fairly common occurrence, these large numbers are leaving scientists concerned and confused. Nearly 8,000 common murres (Uria aalge) were found along the shores of Whittier, Alaska, in early January. Over the New Year's holiday, Alaska experienced four days of gale-force winds from the southeast that resulted in dead birds washing ashore, said Robb Kaler, a wildlife biologist for the Alaska branch of the U.S. Fish and Wildlife Service (USFWS). Scientists have known for some time that the key to surviving strong storm winds is having an energy reserve, according to an expert at Tufts University, and Kaler and his colleagues think that the common murres were not finding enough food this season, which may be why so many didn't make it through the storm. In cases like these, experts typically measure the number of dead birds per kilometer, said Julia Parrish, a professor in the School of Aquatic and Fishery Sciences at the University of Washington in Seattle and executive director of the Coastal Observation and Seabird Survey Team (COASST), which is one of the organizations studying areas where these birds are washing ashore, alongside the USFWS and the U.S. Geological Survey National Wildlife Health Center (NWHC). For the Whittier survey, the final measurements came to approximately 4,600 birds per kilometer, Parrish told Live Science. [5 Mysterious Animal Die-Offs] The common murre is "one of the most abundant and widespread seabirds in Alaska," Kaler told Live Science in an email. While other dead seabirds are being reported on Pacific shorelines, current reports indicate that about 99 percent of the animals are common murres, Kaler said. Seeing a dead seabird on the beach is not altogether unusual, especially during September and October, when the birds are leaving their breeding colonies, Parrish said. However, dead common murres started showing up in Alaska in March. "This is really weird, because that is the beginning of the breeding season," Parrish said. "That's when [seabirds] are [usually] fat and sassy." So far, the NWHC has examined 100 bird carcasses, and most of the birds seem to have died due to starvation, Kaler told Live Science. "While we know murres are starving," Kaler said, "we do not understand the mechanism." There is a chance that saxitoxin, a toxin related to paralytic shellfish poisoning, or domoic acid, a toxin that causes amnesic shellfish poisoning, could be responsible for some of these deaths, he said. But both of these toxins are difficult to detect in birds that have nothing in their stomachs or gastrointestinal tracts, which was the case with most of these animals, Kaler said. In the past, seabird die-off events — in which thousands of birds die in a short period of time — have been associated with strong El Niño events, Kaler said. In 1993, there was another die-off of common murres recorded in the northern Gulf of Alaska, where scientists found about 3,500 dead or dying common murres along the shoreline over a period of six months. Scientists calculated that over that period, about 10,900 bird carcasses actually made it to shore, according to a 1997 study published in the journal Marine Pollution Bulletin. Because researchers were able to monitor only a small fraction of the beaches in Alaska, that study's scientists projected that the actual final death count in 1993 was at least 120,000 birds. With this most recent event, "[w]e assume the die-off is connected to one of the largest oceanographic-atmospheric events, known as 'The Blob,'" Kaler said. This event is the presence of a large area of water that falls well above the average temperature usually observed in the North Pacific, he said. "We do not know how [that] this relates to El Niño or climate warming, but we believe they are factors," Kaler said. The USFWS also noted in a recent bulletin that common murres have turned up at locations as far inland as Fairbanks, Alaska, where the birds have been seen swimming in rivers and lakes. Wildlife biologists consider this to be unusual behavior, since common murres are seabirds and so don't usually show up so far inland, Parrish told Live Science. Additionally, while the die-off has been most visible in Alaska, similar events affected seabird populations in Washington, Oregon and California during the months of September and October, Parrish said. The behaviors of seabirds are often indicators of what is happening in the marine system, said the U.S. Fish and Wildlife Service. Current estimates of the common murre death toll in the recent die-off have suggested that more than 100,000 birds have probably died over the past nine months, and dead birds are likely to continue showing up through the spring, Kaler said. It is important to note that this high death count doesn't mean that common murres are in danger as a species. There are an estimated 2.8 million common murres in Alaska, Parrish said. This means that current estimates of the die-off account for only approximately 3 percent of the total common murre population in the state. That's not to say that the appearance of large numbers of dead birds on beaches isn't of concern, Parrish said. Scientists are speculating that this event indicates a species struggling to deal with altered circumstances, he said. "When there are heat waves during the summertime, you always hear about mortalities in the inner city [from people who don't have air conditioning] and [so] they just have to deal with" the heat, Parrish said. "None of these birds have air conditioning." 6 Extinct Animals That Could Be Brought Back to Life Copyright 2016 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


A highly-devastating bat disease called white-nose syndrome has been detected for the first time in a Northwest bat in Washington, posing a threat for the populations of flying mammals in the state and beyond. According to the Center for Biological Diversity, the little brown bat was discovered on March 11 by hikers on a trail about 30 miles east of Seattle. It is infected by a pathogenic fungus that has already killed 6 million bats in North America. CBD senior scientist Mollie Matteson said the event is a wake-up call for land-managers in the West to do everything they can to keep the bat disease from spiraling out of control -- before it is too late. "It's shocking and disturbing to see this disease reach Washington and indeed the western United States," said Matteson. Veterinarian Katherine Haman said the hikers found the bat alive, but it was very weak and unable to fly. The animal was taken to a PAWS shelter, where it died in the cage two days after. The state's wildlife agency sent the bat to the U.S. Geological Survey's National Wildlife Health Center in Wisconsin, where scientists confirmed that the bat was indeed infected by white-nose syndrome. The deadly disease has caused dramatic declines among populations of several bat species, including the Indiana bat, the northern long-eared bat, the tricolored bat, and the little brown bat. Experts say it is the worst wildlife health crisis in recent years, resulting to 100 percent mortality rates among bats in affected caves. Seven bat species have been known to be afflicted with white-nose syndrome. Unfortunately, there is no known cure. The disease's first detection in Western U.S. represents a "game-changer," said wildlife biologist Jeremy Coleman. The closest state with a confirmed detection of the pathogenic fungus is 1,250 miles away in Nebraska. Humans and other animals are not known to be susceptible to white-nose syndrome. Meanwhile, scientists have raised several questions: how many bats in the Northwest are infected? How long has the disease been in the state? How did it reach the state? One possible explanation is that spelunkers and miners transported the fungus on gear or shoes, experts said. "This disease just made a jump of more than 1,000 miles, so it's pretty reasonable to think this could be a human-caused transmission," said Matteson. In 2010, the CBD filed a petition to close all caves and abandoned mines on federal lands as a precautionary measure. Such closures would decrease disturbance of hibernating bats. Matteson said the news is heartbreaking because wildlife and land managers could have done more to stem the spread, such as prohibiting nonessential cave access into land caves. "They could have passed rules requiring that no caving gear or clothing from WNS-positive states be allowed in caves in unaffected states," added Matteson.


News Article | March 12, 2016
Site: news.yahoo.com

Wildlife biologists Rob Kaler of the U.S. Fish and Wildlife Service and Sarah Schoen of the U.S. Geological Survey examine body parts of a common murre during a necropsy on Friday, March 11, 2016, in Anchorage, Alaska. Kaler and Schoen are among scientists attempting to find out the reason for a massive common murre die-off in the North Pacific that began one year ago. (AP Photo/Dan Joling) More Measurements of its beak and leg indicated it hatched in June. Its stomach and breast showed how it died. The 3-inch-long stomach was empty, and the pectoral muscles that powered its wings, allowing it to "fly" underwater after forage fish, were emaciated. "As the bird starves, the body eats the muscle for energy," Schoen said. "The muscle becomes more and more concave." Schoen, a wildlife biologist for the U.S. Geological Survey, and Rob Kaler, a biologist for the U.S. Fish and Wildlife Service, on Friday performed necropsies on common murres, part of an effort by dozens of scientists to explain the massive die-off of common murres that began one year ago. Common murres are one of the northern hemisphere's most common seabirds. The Alaska population is estimated at 2.8 million out of a world population of 13 to 20.7 million birds. Awkward on land, common murres can dive to 600 feet hunting fish or krill. Die-offs have occurred before but not on this magnitude. Common murres routinely live 20-25 years but have a metabolism rate so high that they can use up fat reserves and drop to a critical threshold for starvation, 65 percent of normal body rate, in three days of not eating. Abnormal numbers of carcasses, all showing signs of starvation, began washing ashore on Alaska beaches in March 2015. Numbers spiked to alarming levels in early winter. The confirmed carcass count is now up to 36,000, Schoen said. That's far higher than previous common murre die-offs and many beaches have not been surveyed. New common murre carcasses continue to be recorded, most recently on Kodiak, Alaska Peninsula communities and the Pribilof Islands. "The ravens and eagles make it easy to see that birds are continuing to die and get washed up," Kaler said. The scavengers eat the dead murres. No one is offering an estimate of the total deaths. In previous die-off, researchers estimated that only about 15 percent of carcasses reach shores, which means the total may be in the hundreds of thousands. The USGS's National Wildlife Health Center in Madison, Wisconsin, is testing murres for signs of disease or parasites. Though the murres appear to have starved, researchers wonder if something caused them to quit eating or to be less successful funding food. Schoen and Kaler were looking for broad, general information about body conditions. They extracted samples of liver, which can indicate what the bird ate a week before it died, and muscle, which can indicate what it ate in the last month. They took feather samples for isotope analysis regarding diet. Sudden diet changes could be telling. If they were eating at one level of the food web, and a regular food source became unavailable, it could provide insight into the deaths, Schoen said. Schoen in January necropsied 61 birds found in Prince William Sound. Most were birds under 2 years old and 77 percent were female. Female deaths are significant because of the possible effect on the overall population. The sampled birds also were heavier than birds sampled in a 1993 die-off, Schoen said. "So it doesn't look like just starvation is killing them," Schoen said. "It looks like there's something else that could be tipping them over the edge." That reason could be a toxin birds ingested from tainted algae. The reason could be severe winter storms that kept weakened birds from feeding. Or it could be something unknown. Federal agencies don't have dedicated funding to solve the common murre mystery but will continue investigating as time allows. Schoen and Kaler said they hope to continue the sampling work with carcasses collected from other areas of Alaska.


News Article | April 1, 2016
Site: www.sciencenews.org

A sick bat caught by hikers not far from Seattle has now been confirmed to have the first case west of the Rockies of the deadly bat disease white-nose syndrome. First noticed in North America in the winter of 2006-2007, the disease exterminated some whole colonies of hibernating bats on the East Coast, though some species have proved less susceptible.  White-nose syndrome has now swept from coast to coast, the U.S. Geological Survey confirmed March 31. So far the USGS’s National Wildlife Health Center has only confirmed the one case, in a little brown bat (Myotis lucifugus) that hikers found near North Bend, Wash., on March 11 and took to an animal welfare center for care. Genetic testing identified it as a little brown bat most likely from the West instead of an accidental hitchhiker that crossed the Rockies in a truck or cargo container, Jeremy Coleman of the U.S. Fish and Wildlife Service said at a press conference. Just how the disease reached Washington isn’t clear yet. Twenty-seven other states and five Canadian provinces have reported it, but what was previously the most western location, in Nebraska,was more than 1,000miles away. The fungus causing the disease can spread bat-to-bat or can ride along on travelers’ outdoor gear. Watch for updated decontamination procedures in early April, Coleman said.


News Article | March 13, 2016
Site: phys.org

Measurements of its beak and leg indicated it hatched in June. Its stomach and breast showed how it died. The 3-inch-long stomach was empty, and the pectoral muscles that powered its wings, allowing it to "fly" underwater after forage fish, were emaciated. "As the bird starves, the body eats the muscle for energy," Schoen said. "The muscle becomes more and more concave." Schoen, a wildlife biologist for the U.S. Geological Survey, and Rob Kaler, a biologist for the U.S. Fish and Wildlife Service, on Friday performed necropsies on common murres, part of an effort by dozens of scientists to explain the massive die-off of common murres that began one year ago. Common murres are one of the northern hemisphere's most common seabirds. The Alaska population is estimated at 2.8 million out of a world population of 13 to 20.7 million birds. Awkward on land, common murres can dive to 600 feet hunting fish or krill. Die-offs have occurred before but not on this magnitude. Common murres routinely live 20-25 years but have a metabolism rate so high that they can use up fat reserves and drop to a critical threshold for starvation, 65 percent of normal body rate, in three days of not eating. Abnormal numbers of carcasses, all showing signs of starvation, began washing ashore on Alaska beaches in March 2015. Numbers spiked to alarming levels in early winter. The confirmed carcass count is now up to 36,000, Schoen said. That's far higher than previous common murre die-offs and many beaches have not been surveyed. New common murre carcasses continue to be recorded, most recently on Kodiak, Alaska Peninsula communities and the Pribilof Islands. "The ravens and eagles make it easy to see that birds are continuing to die and get washed up," Kaler said. The scavengers eat the dead murres. No one is offering an estimate of the total deaths. In previous die-off, researchers estimated that only about 15 percent of carcasses reach shores, which means the total may be in the hundreds of thousands. The USGS's National Wildlife Health Center in Madison, Wisconsin, is testing murres for signs of disease or parasites. Though the murres appear to have starved, researchers wonder if something caused them to quit eating or to be less successful funding food. Schoen and Kaler were looking for broad, general information about body conditions. They extracted samples of liver, which can indicate what the bird ate a week before it died, and muscle, which can indicate what it ate in the last month. They took feather samples for isotope analysis regarding diet. Sudden diet changes could be telling. If they were eating at one level of the food web, and a regular food source became unavailable, it could provide insight into the deaths, Schoen said. Schoen in January necropsied 61 birds found in Prince William Sound. Most were birds under 2 years old and 77 percent were female. Female deaths are significant because of the possible effect on the overall population. The sampled birds also were heavier than birds sampled in a 1993 die-off, Schoen said. "So it doesn't look like just starvation is killing them," Schoen said. "It looks like there's something else that could be tipping them over the edge." That reason could be a toxin birds ingested from tainted algae. The reason could be severe winter storms that kept weakened birds from feeding. Or it could be something unknown. Federal agencies don't have dedicated funding to solve the common murre mystery but will continue investigating as time allows. Schoen and Kaler said they hope to continue the sampling work with carcasses collected from other areas of Alaska. Explore further: New evidence suggests some birds gave up flight to become better swimmers


News Article | March 14, 2016
Site: www.biosciencetechnology.com

Measurements of its beak and leg indicated it hatched in June. Its stomach and breast showed how it died. The 3-inch-long stomach was empty, and the pectoral muscles that powered its wings, allowing it to "fly" underwater after forage fish, were emaciated. "As the bird starves, the body eats the muscle for energy," Schoen said. "The muscle becomes more and more concave." Schoen, a wildlife biologist for the U.S. Geological Survey, and Rob Kaler, a biologist for the U.S. Fish and Wildlife Service, on Friday performed necropsies on common murres, part of an effort by dozens of scientists to explain the massive die-off of common murres that began one year ago. Common murres are one of the northern hemisphere's most common seabirds. The Alaska population is estimated at 2.8 million out of a world population of 13 to 20.7 million birds. Awkward on land, common murres can dive to 600 feet hunting fish or krill. Die-offs have occurred before but not on this magnitude. Common murres routinely live 20-25 years but have a metabolism rate so high that they can use up fat reserves and drop to a critical threshold for starvation, 65 percent of normal body rate, in three days of not eating. Abnormal numbers of carcasses, all showing signs of starvation, began washing ashore on Alaska beaches in March 2015. Numbers spiked to alarming levels in early winter. The confirmed carcass count is now up to 36,000, Schoen said. That's far higher than previous common murre die-offs and many beaches have not been surveyed. New common murre carcasses continue to be recorded, most recently on Kodiak, Alaska Peninsula communities and the Pribilof Islands. "The ravens and eagles make it easy to see that birds are continuing to die and get washed up," Kaler said. The scavengers eat the dead murres. No one is offering an estimate of the total deaths. In previous die-off, researchers estimated that only about 15 percent of carcasses reach shores, which means the total may be in the hundreds of thousands. The USGS's National Wildlife Health Center in Madison, Wisconsin, is testing murres for signs of disease or parasites. Though the murres appear to have starved, researchers wonder if something caused them to quit eating or to be less successful funding food. Schoen and Kaler were looking for broad, general information about body conditions. They extracted samples of liver, which can indicate what the bird ate a week before it died, and muscle, which can indicate what it ate in the last month. They took feather samples for isotope analysis regarding diet. Sudden diet changes could be telling. If they were eating at one level of the food web, and a regular food source became unavailable, it could provide insight into the deaths, Schoen said. Schoen in January necropsied 61 birds found in Prince William Sound. Most were birds under 2 years old and 77 percent were female. Female deaths are significant because of the possible effect on the overall population. The sampled birds also were heavier than birds sampled in a 1993 die-off, Schoen said. "So it doesn't look like just starvation is killing them," Schoen said. "It looks like there's something else that could be tipping them over the edge." That reason could be a toxin birds ingested from tainted algae. The reason could be severe winter storms that kept weakened birds from feeding. Or it could be something unknown. Federal agencies don't have dedicated funding to solve the common murre mystery but will continue investigating as time allows. Schoen and Kaler said they hope to continue the sampling work with carcasses collected from other areas of Alaska.


News Article | March 15, 2016
Site: www.sciencenews.org

There’s a deadly fungus spreading among snakes in the United States. But don’t cheer. As much as snakes might frighten us, they’re important players in the ecosystem, and we really don’t want to lose them. In 2006, scientists discovered some odd skin infections among snakes in declining populations in New Hampshire. Soon after, fungal infections were found in massasauga rattlesnakes in Illinois, and the disease appeared to be bad enough that it might eradicate the species from the entire state. Over the next decade, researchers found the fungus in more and more states in the eastern United States, in some cases killing up to 90 percent of infected snakes. With the discovery earlier this month of the disease in a young broad-banded watersnake in Louisiana, snake fungal disease has now been found in a total of 14 snake species and 16 states. And scientists are worried that the situation could get worse. For years, the fungus Ophidiomyces ophiodiicola was the suspected culprit behind the disease, but scientists couldn’t tell whether the pathogen was causing the skin lesions they were seeing on dead snakes or if the fungus had just taken advantage of lesions that were there from some other cause. But last year, Jeffrey Lorch of the U.S. Geological Survey’s National Wildlife Health Center in Madison, Wis., and colleagues managed to nail down the link between the fungus and the disease. They infected corn snakes in the lab and observed skin lesions that were identical to those found in wild snakes that had the disease. The experiment also gave some clues as to why snake fungal disease can be deadly: In the lab, infected snakes molted more often, and some exhibited behaviors that, in the wild, could be troublesome, such as anorexia and hanging out in more open areas. “Chronic O. ophiodiicola infections could have significant impacts on host energy balance and body condition,” Lorch and his colleagues wrote in their study, published November 17 in mBio. “Failure of infected wild snakes to procure sufficient food could result in a feedback loop that reduces host defenses, facilitating more severe infections that further compromise a snake’s ability to obtain prey.” That fungus shares many similarities with another fungus spreading across the United States — Pseudogymnoascus destructans, which causes white-nose syndrome in bats. Like P. destructans, O. ophiodiicola is a soil fungus, and it has many of the same enzymes that have helped white-nose syndrome persist, researchers reported in the October Fungal Ecology. Researchers have also found parallels to the chytrid fungi spreading among frogs and salamanders. As much as people don’t like snakes, they would probably like life without snakes a lot less. Snakes eat rodents, so if you don’t want the mice and rat populations to get out of control, snakes are necessary. (Call them a “necessary evil,” if you like. The snakes won’t mind.) Snake fungal disease isn’t the only worry for snake populations. A 2010 study in Biology Letters found some worrying evidence of a global decline in snakes, possible related to habitat deterioration, lack of prey and, maybe, climate change. But the status of the world’s snakes right now isn’t really clear. There’s so little known about so many snake species that scientists can’t say how bad the situation might be.


News Article | November 22, 2015
Site: news.yahoo.com

FILE - In this July 31, 2015 file photo, two rattlesnakes hide in a crack in a rock at an undisclosed location in western Rutland County, Vt. Jeffrey Lorch, a microbiologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wisc., said in a paper published Tuesday, Nov. 17, 2015, that he has identified the fungus that has been infecting some snake species in the eastern United States. Vermont's small population of rattlesnakes is being threatened by the fungus that was first observed by scientists a few years earlier. (AP Photo/Wilson Ring, File) More MONTPELIER, Vt. (AP) — A fungus has been identified as the cause of a mysterious ailment that has been infecting some snake species in the eastern United States, threatening some isolated snake populations such as the timber rattlesnakes found in western Vermont. Knowing for sure the cause of what has become known as snake fungal disease will make it possible for scientists to begin searching for the reason it has emerged and what, if anything, can be done to stop its spread or to protect snakes from it, said Jeffrey Lorch, a microbiologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wisconsin. Scientists still don't know for sure if the fungus, ophidiomyces ophiodiicola, was recently introduced to North America or if it has been here all along and something is now making it emerge and infect a number of snake species in at a number of states in the East and Midwest. In the laboratory tests that led scientists to link the fungus with the disease, infected snakes changed their behavior in ways that could have made them more susceptible to predators or the environment and scientists are trying to determine if climate change is playing a role. "These cold-blooded animals are going to be much more sensitive to even minor changes in climate," said Lorch, the lead author on the study published Nov. 17 in the journal MBio that linked the fungus to the disease. "And that might be why they are the canary in the coal mine. If this is a disease that is climate-change related, there is some concern that it is the tip of the iceberg." Biologists have compared the appearance of snake fungal disease in the last decade to the fungus that causes white nose syndrome in bats, which since 2006 has killed millions of the creatures and continues to spread across North America. In some areas snake fungal disease has been quite lethal while in others most infected snakes recover. For example, while timber rattlesnakes in the northeast have been hit hard, timber rattlesnakes populations in the upper Midwest seem to be coping with the infection, Lorch said. "It's potentially fairly complex, trying to find if there's that threshold level that these populations might reach where conditions are just suddenly right for what might normally be an annoyance or just a mild infection to become deadly," Lorch said. Although snake fungal disease affects a number of species, it's especially threatening to snake species such as slow-reproducing timber rattlesnakes that live in small, isolated populations with little genetic diversity, such as those found in Vermont, New Hampshire, Massachusetts and New York. Among other states where the fungus has been found are Illinois, Florida, Minnesota, New Jersey, New York, Ohio, Tennessee and Wisconsin. Doug Blodgett, the snake specialist for the Vermont Department of Fish and Wildlife, says they've confirmed the fungal disease in the state's rattlesnake population as well as the eastern rat snake and they suspect it in the milk snake. The biggest concern is for the state's timber rattlesnakes, estimated at several hundred in two locations not far from southern Lake Champlain. "None of it's good. It's not a good thing," Blodgett said. "The reason this has bigger implications for the rattlesnake is because we have so few rattlesnakes left compared to these other species."


News Article | November 23, 2015
Site: www.biosciencetechnology.com

A fungus has been identified as the cause of a mysterious ailment that has been infecting some snake species in the eastern United States, threatening some isolated snake populations such as the timber rattlesnakes found in western Vermont. Knowing for sure the cause of what has become known as snake fungal disease will make it possible for scientists to begin searching for the reason it has emerged and what, if anything, can be done to stop its spread or to protect snakes from it, said Jeffrey Lorch, a microbiologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wisconsin. Scientists still don't know for sure if the fungus, ophidiomyces ophiodiicola, was recently introduced to North America or if it has been here all along and something is now making it emerge and infect a number of snake species in at a number of states in the East and Midwest. In the laboratory tests that led scientists to link the fungus with the disease, infected snakes changed their behavior in ways that could have made them more susceptible to predators or the environment and scientists are trying to determine if climate change is playing a role. "These cold-blooded animals are going to be much more sensitive to even minor changes in climate," said Lorch, the lead author on the study published Nov. 17 in the journal MBio that linked the fungus to the disease. "And that might be why they are the canary in the coal mine. If this is a disease that is climate-change related, there is some concern that it is the tip of the iceberg." Biologists have compared the appearance of snake fungal disease in the last decade to the fungus that causes white nose syndrome in bats, which since 2006 has killed millions of the creatures and continues to spread across North America. In some areas snake fungal disease has been quite lethal while in others most infected snakes recover. For example, while timber rattlesnakes in the northeast have been hit hard, timber rattlesnakes populations in the upper Midwest seem to be coping with the infection, Lorch said. "It's potentially fairly complex, trying to find if there's that threshold level that these populations might reach where conditions are just suddenly right for what might normally be an annoyance or just a mild infection to become deadly," Lorch said. Although snake fungal disease affects a number of species, it's especially threatening to snake species such as slow-reproducing timber rattlesnakes that live in small, isolated populations with little genetic diversity, such as those found in Vermont, New Hampshire, Massachusetts and New York. Among other states where the fungus has been found are Illinois, Florida, Minnesota, New Jersey, New York, Ohio, Tennessee and Wisconsin. Doug Blodgett, the snake specialist for the Vermont Department of Fish and Wildlife, says they've confirmed the fungal disease in the state's rattlesnake population as well as the eastern rat snake and they suspect it in the milk snake. The biggest concern is for the state's timber rattlesnakes, estimated at several hundred in two locations not far from southern Lake Champlain. "None of it's good. It's not a good thing," Blodgett said. "The reason this has bigger implications for the rattlesnake is because we have so few rattlesnakes left compared to these other species."


News Article | December 27, 2016
Site: www.techtimes.com

A fungal disease known to kill millions of bats in North America can now be tracked using a newly identified fungus-infecting virus. In a study featured in the journal PLOS Pathogens, researchers from Pennsylvania State University discussed how they were able to identify a virus harbored by the Pseudogymnoascus destructans fungus. P. destructans is known to be the cause of the white-nose syndrome (WNS) among bats, which has already killed as many as 6 million of the flying mammals in North America since it was first discovered in 2006. Prof. Marilyn Roossinck and her colleagues at Penn State believe that the virus that they isolated could be used as a marker to monitor the spread of WNS to other bats. According to the U.S. Geological Survey's National Wildlife Health Center, WNS is a highly contagious disease known to affect hibernating bats. It gets its name from the white fungus P. destructans that infects the skin on the ears, muzzle, and wings of the animals. Millions of insect-eating bats have already been killed by the disease in 29 U.S. states and five Canadian provinces since the winter of 2007 to 2008. Researchers have now also detected WNS in Rhode Island and Washington. While WNS can infect several bat species, those living in the northeast have been found to be particularly at risk. The mortality rate for the disease can reach as high as 99 percent among these species. Animal conservationists are concerned that the high mortality rate could severely affect the ecological balance in the country since bats help keep populations of insect pests, such as mosquitoes, in check. To help understand more about the white-nose syndrome, Roossinck and her team analyzed 62 isolates of P. destructans, including 35 collected from the U.S., 17 from Europe, and 10 from Canada. They discovered that only samples taken from North America have the virus infection they were looking for. Since the P. destructans fungus is clonal, Roossinck said it is identical wherever the organism exists in North America. This makes it difficult for researchers to determine how it is able to spread. However, the researchers found that the virus the fungus harbors has several variations. While the viruses in the isolates they examined from Pennsylvania were similar, those found in isolates taken from Canada and other areas differed from each other. The researchers said fungi are not readily affected by fungal viruses. This means that the differences in viral genome they identified could occur after the virus begins to evolve within fungal isolates, making it a good candidate as a marker. "We believe the differences in the viruses reflect the movement of the fungus, and this viral variability should enable us to get a better handle on how the disease is spreading," Roossinck pointed out. The identified virus is not known to cause white-nose syndrome. However, the researchers have yet to prove that it influences the virulence of the disease. Roossinck said it is difficult to determine the virulence of WNS in terms of bat infection since there are only a few of the animals left to study. They also have yet to devise an experimental system that would work for such an endeavor. The researchers were able to eliminate the virus from one of the fungal isolates they retrieved. This has given them a virus-free isolate that they can use to compare biochemical changes in the virus-infect isolates they still have. Roossinck and her colleagues now plan to use their findings to come up with strategies on how to control the spread of white-nose syndrome in North America and help save the bats that are still left. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.

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