Monday, May 19, 2008

Deadly syndrome spreading among bats in Northeast; could affect agriculture

Thousands of bats in the northeastern U.S. have perished since Fberuary from a mysterious disease known as white-nose syndrome. The deaths could have negative impacts, especially on agriculture. (Map by Cal Butchkoski, Pennsylvania Game Commission)
The syndrome was first observed in caves near Albany, N.Y., by the New York State Department of Environmental Conservation in February 2007. A white substance was present on the heads and wings of dead and hibernating bats. Now that spring is here and people are more active outdoors, the U.S. Geological Survey issued a Wildlife Health Bulletin urging wildlife and conservation officials throughout the U.S. to be on the lookout for the syndrome and to report suspected cases of the disease.

"Bats are an important part of our ecosystem," says the U.S. Fish and Wildlife Service. "One bat eats as many as 3,000 flying insects a night during the summer months. Because females produce just one pup a year, the plunging number of bats — apparently as many as 90 percent loss in some hibernacula — translates into a crisis in bat populations in four states with no end in sight and potentially far-reaching effects, an ecological disaster in the making."

"The most common findings in the bats have been emaciation and poor body condition," reports Science Daily. "Many of the bats examined had little or no body fat; some exhibited changes in the lung that have been difficult to characterize; and a majority had microscopic fungi on their bodies. The white substance (as illustrated in the photograph by Alan Hicks) observed on some bats may represent an overgrowth of normal fungal colonizers of bat skin during hibernation and could be an indicator of overall poor health, rather than a primary pathogen. Scientists from a variety of agencies are investigating underlying environmental factors, potential secondary microbial pathogens and toxicants as possible causes."

Scott Darling, a bat biologist for the Vermont Fish and Wildlife Department, told WCAX News, "When you do the math and make the calculations of some 500,000 bats being affected by white nose syndrome, that adds up to literally 2 billion insects per night that won't be eaten by those bats."

Darling estimates that, based on preliminary findings, the syndrome has an expected fatality rate of 90 percent and has affected approximately 600,000 bats in the region. "At this point, I consider all of Vermont affected," he said. "We have upwards of 25 confirmed sites in New York, Vermont, Massachusetts and Connecticut, and we have suspected it in some sites in Pennsylvania." Large-scale wildlife deaths should be reported to the USGS here.

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