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Madison, WI, United States

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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.


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


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."


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
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.

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