Thursday, December 12, 2013
The U.S. military stored nuclear weapons in half-buried concrete bunkers in northern Maine for nearly 40 years, but the Cold War is long over and the Soviet Union no longer exists, meaning the bunkers are available.
Unused nuclear weapons bunkers are being readied for use as artificial caves for bat hibernation.
Photos courtesy of U.S. Fish and Wildlife Service
A brown bat with white nose syndrome is shown above. The fungal infection has killed more than 5.5 million bats in eastern North America since it was first detected in upstate New York in 2006. Researches are investigating various ways to prevent the spread of the disease.
So federal wildlife officials plan to use the bunkers to take aim at a different enemy: white-nose syndrome, a fungal disease that has wiped out nearly 90 percent of little brown bats in the eastern third of the nation.
Forty-six bunkers that once stored bombs such as the Mark 4 (Fat Man), Mark 6 and Mark 17 -- refinements of the bombs dropped on Hiroshima and Nagasaki -- soon may provide hibernation sites for little brown bats, which are rapidly disappearing because of the cold-tolerant fungus that causes white-nose syndrome.
The disease, which has killed an estimated 5 million to 6.5 million bats nationwide, strikes most fiercely when the bats are hibernating. From October to late March or early April, bats remain in a state of torpor for long periods. Their metabolism slows and immune systems weaken because they are not feeding.
But long before bats start swarming for hibernation this fall, wildlife officials in the Aroostook National Wildlife Refuge in Limestone will be working to fabricate two artificial caves, each 15 feet high, 25 feet wide and 80 feet long.
Over the next couple of weeks, officials will try to "sterilize" the first of the old bunkers to ensure that the fungus, newly reclassified as Pseudogymnoascus destructans, has been eliminated and the structure provides a safe refuge for the bats, said assistant refuge manager Steve Agius of the U.S. Department of Interior's Fish and Wildlife Service.
The second bunker will be left as is to mimic a natural cave and serve as a control structure to gauge whether the manipulated environment in the other hut is having any positive effect.
This experiment in survival for flying mammals marks a big transformation for the 8,200-square-mile wildlife refuge, located on part of the former Loring Air Force Base in Aroostook County. From the late 1950s into the 1980s, the bunkers housed nuclear weaponry because the base was the nearest point to Moscow in the U.S., Agius said.
The wildlife refuge, established in 1998, returned the land to conserved wild space for animals, which is the U.S. Fish and Wildlife Service's mandate on all refuges.
But this program has taken the concept a step further, because the existing environment is being manipulated for the benefit of the bats. And it occurs at a critical juncture in the spread of white-nose syndrome, when populations of little brown bats are so heavily infected that they could be wiped out, said Ann Froschauer, spokeswoman for the U.S. Fish and Wildlife Service, which is tracking the disorder nationwide.
Bats afflicted with white-nose syndrome suffer from ulcerated, scarred or dying wing membrane tissue, possibly from being penetrated by the fungus. Infected bats essentially starve to death, but scientists have not yet figured out exactly why, according to the wildlife officials with the Department of the Interior.
The disorder is also thought to prompt bats to alter their winter behavior, causing them to move to the entrance of their hibernation caves or even emerge and fly around during daylight hours, scientists have observed. Because bats normally do not waken during hibernation to eat -- rousing only occasionally to drink water -- the extra activity reduces their bodies' fat stores. Some bats cease to respond at all to stimuli, and many have been found dead both inside and outside caves.
Transmitted primarily from bat to bat, the syndrome is of particular interest to medical researchers because bats are significant predators of mosquitoes, which are vectors of disease in birds, mammals and humans. Bats also serve as major crop pollinators and provide the equivalent of $2 billion to $3 billion a year of insect pest control.
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click image to enlarge
Nuclear weapons bunkers in Aroostook County are being repurposed as artificial caves for bat hibernation. Two structures will be used this winter, one as a study control.