APRIL 22, 2010 -- It's the grim news that wildlife biologists have dreaded all winter: Officials from the state Department of Environmental Protection will confirm this morning that population counts of hibernating bats show that they continue to be decimated by the disease known as white-nose syndrome, and that some species might even be threatened with extinction.
"The numbers are devastating for Connecticut bats," said one DEP official. "The onslaught of white-nose just won't stop."
In Connecticut and throughout the Northeast, species such as the little brown bat, northern long-eared bats and pipistrelle bats have proved to be especially vulnerable. Little browns were once considered Connecticut's most common bat species. But in one Litchfield County cave from 2007 to 2009, the population of little brown bats plummeted from 2,320 to 108, results that are expected to be even more ominous when the DEP announces its cave counts today.
Scientists in Connecticut and elsewhere also are worried about the Indiana bat, which was declared endangered in 1967 and appeared to be making a painfully slow comeback before white-nose arrived in 2006.
"In the five states where most of my research has centered, little brown bats and Indiana bats are among the most threatened by [white-nose syndrome] - meaning their populations could either be seriously decimated or become extinct," U.S. Department of Agriculture ecologist Susan Loeb told UPI.
"Historically, little brown bats were quite common," she said, "but the species appears to be especially susceptible to the fungus and is being hit hard in the states where [white-nose syndrome] has taken hold."
Bats are one of nature's most efficient filters. Individual bats can consume as many as 1,200 mosquitoes and flies an hour as they flit around at night, making them a vital insect-control species. Some species - such as Connecticut's big brown bat - also are critical to agriculture because they consume large hatches of insects and moths that swarm upon crops.
Since 2006, when hibernating bats in a cave west of Albany were found coated with a chalky fungus that caused them to interrupt their hibernation and burn up their fat reserves, the condition has killed more than 1 million bats in the Northeast. The U.S. Geological Survey has called the bat die-off "the most precipitous decline of North American wildlife caused by infectious disease in recorded history."
Hopscotching from state to state as bats congregate in caves every winter, white-nose has now been confirmed in Tennessee, which has one of the most concentrated bat populations in the world, and it could infect bats throughout the United States within a few years unless checked.
The rapid spread of the fungus across a broad swath of North America is what concerns scientists most. Last week, the deadly fungus was confirmed in bats in the Canadian provinces of Ontario and Quebec, and biologists also found white-nose on a little brown bat in the Great Smoky Mountains National Park in Tennessee.
The bat scourge apparently has now crossed another critical threshold - the Mississippi River. On Monday, scientists confirmed its presence on a bat in Missouri, although the bat's health apparently was not yet affected.
"Oh, cripes, this is really getting bad now," said Alan Hicks, the endangered species specialist with the New York State Department of Environmental Conservation, whose team initially identified white-nose syndrome.
"Finding this fungus across the Mississippi can put our efforts behind by a whole year," he said Monday. To combat the disease, Hicks said, scientists need healthy, uncontaminated bats to use as laboratory controls in experiments. But the infection of the Midwest population now eliminates this control group.
Research scientists working to identify the source of the fungus and learn why it is killing bats wonder whether they have enough time to find a solution. Geomyces destructans, the fungus found coating the faces, wings and legs of bats, also has been identified on European bats but apparently causes them no harm. This might be because European bats have developed resistance to the fungus or that populations already have been decimated, leaving only especially hearty bats.
"We don't have the luxury of time," Hicks said. "We've been working on cancer in humans for 50 or 60 years and made some progress, but it's not as if the species will be gone before we find a cure. Well, we are in year four now with white-nose, are nowhere close to understanding what's happening and the bats are disappearing fast."
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