Eastern U.S. bats on verge of extinction

Bats in eastern parts of the United States and Canada are dying out from a new disease.

White-nose syndrome, named for the white fungi on muzzles and wings, makes bats restless, depleting their reserves of body fat during hibernation. The fungi – first found in February 2006 in a New York cave – are considered the likely cause of the disease.

According to a Wired article, biologist Winifred Frick said: "Yes, we had the empirical observations that cave floors were littered with dead bats. [...] But nobody had quantified the impact to the populations. We didn’t know what those die-offs meant to population viability as a species."

Frick and her colleagues analyzed the last 30 years of population data for the most common and most-studied species of bat in North America, the little brown bat (Myotis lucifugus). If recent trends continue, the researchers predict a "99 percent chance of regional extinction of little brown myotis within the next 16 years."

A little brown bat with white nose syndrome.

The little brown bat is among seven species now affected, including two bat species already endangered. 25 of the 46 U.S. bat species hibernate in caves and thus could be affected by the disease.

"Bats affected by this disease are all insect-eating species, and an individual bat can consume its body weight in insects every night, including some consumption of pest insects," Frick noted, as quoted by the press release from University of California, Santa Cruz.

One of the study's co-authors, Thomas Kunz, estimated before the outbreak that the value of insect-eating bats in an eight-county region of southwest Texas is about $1 million in pesticide costs alone.

The disease is spreading; 2010 saw infected bats found in the inland states of Tennessee and Oklahoma. But research funding remains scarce. Last year, the U.S. Congress approved US$1.9 million for 2010 for research in the cause and solutions for the syndrome. It was a dramatic increase from the initial allocation of $500,000, but nowhere near the five-year budget of $55 million requested by Kunz and other scientists.

"Without research funding raised by Bat Conservation International, the science would be at a crawl," writes Wired author Bandon Keim. Despite the limitations, Frick said scientists "are trying as hard as possible to find a solution to this devastating problem."

The study concludes that "the rapid decline of a common bat species from white-nose syndrome draws attention to the need for increased research, monitoring, and management to better understand and combat this invasive wildlife disease."