Not Since Passenger Pigeons: Collapse of the Bats
One Million Bats Felled by a Possible Human-Caused Fungus
Dr. DeeAnn Reeder, Assistant Professor of Biology from Bucknell College, is a leading researcher of bat immune systems and is studying a deadly fungus called white nose syndrome (because of the white powder that appears on afflicted bat’s noses). Dr. Reeder explains that one million bats—the number already felled by the fungus—consume some 700 tons of insects on an annual basis. A recent Science study estimated that bats provide more than $3.7 billion in pest-control services to U.S. agriculture every year. That same study also predicted that the most common bat species, the little brown bat, might become extinct in the Eastern U.S. by 2028. “Within our lifetimes,” says Dr. Marianne Susan Moore, one of Reeder’s associates, “never has there been such a rapid and massive decline in a population of wild animals as a result of disease.” The late Thomas Kunz, Professor of Biology at Boston University and a leading white nose syndrome researcher, wrote, “I think you have to go back to the 1800s, to the loss of the passenger pigeon, to find something similar. And then, we didn’t know what we were doing.”
Today in caves across the east and parts of the Midwest, human activity might be contributing to the demise of bats. White nose syndrome has spread to 19 states and 4 Canadian provinces, and is estimated to have killed over one million bats. Somehow a deadly fungus was introduced into bat habitats; one theory is an American spelunker unwittingly brought it from European caves via contaminated equipment. European bats have a resistance to the disease, the theory goes, but North American bats, do not. By studying the endocrine system of normal and diseased bats, Dr. Reeder and her team found that white-nose syndrome affects bats' hibernation, causing them to starve to death. One theory is that bats in cooler temperatures might have higher survival rates. Humans could alter temperatures in some mines, by changing the airflow into entrances. Conservationists in Tennessee are planning to construct an artificial cave and keep it fungus free; in New Hampshire, biologists are studying bats hibernating in World War II-era bunkers, hoping the conditions are conducive to survival. .
Passenger pigeons and bats are linked in ways other than having abundant populations that rapidly crashed. Another scientist is trying to help Dr. Reeder through the study of ancient DNA. Dr. Rob Fleischer of the Smithsonian Conservation Biology Institute and a group of colleagues recently extracted passenger pigeon DNA to study the relationship of passenger pigeons to other pigeons. Fleischer is now planning to study the genes of long dead bats to see if he can find signs of pathogens similar to white nose syndrome..
“On my worst days, I feel like we’re working our tails off just to document an extinction,” says Reeder. “But somehow in really teasing apart all of this. . .we may find something really important. . . that might help.” Bats are hunted by birds of prey and snakes. Their guano is an integral element of cave ecosystems. And their absence would wreak havoc in agricultural production. As a strand within the web of life, they contribute to the health of the whole. And we are part of that web.
Compiled by David Mrazek, of Waubansee Productions. He is an award-winning documentary filmmaker who is directing and co-writing, From Billions to None, as a component of Project Passenger Pigeon. This material will be part of the treatment for the film.