An emerging contagious disease called White Nose Syndrome (WNS) is
killing hundreds of thousands of bats a year in the Northeastern United
States, and scientists worry that some species could become extinct in
Bats with the frothy looking white material on
their noses, skin and wing membranes were first photographed in a cave
in New York state in 2006, and biologists began to study the fungal WNS
in 2007. Scientists estimate it has killed a million bats in 10
states, with potentially severe ecological and economic consequences.
In most species, female bats produce only one baby a year, so population
losses do not quickly recover.Thomas Kunz
is Director of the Center for Ecology and Conservation Biology
at Boston University. DeeAnn Reeder
is an assistant biology professor at Bucknell University who
specializes in comparative behavior and physiology of mammals. They
discussed Bats in Peril on Radio Times,
broadcast by National Public Radio.
The two professors say bats are a keystone species,
meaning that they have a disproportionate impact on their surroundings,
like the architectural piecesat the apex of an arch that keep the
other elementsin place. In ecology and architecture, the loss of those
pieces brings collapse. Bats are unusual, numerous, and diverse, the
profesors say.They are the only mammals that fly. One out of every five
mammals is a bat, and their diets and habits vary widely. Seventy
percent of bat species feed on insects that feed on agricultural crops
and forests. Professor Kunz explains the million bats lost to disease
would have eaten 694 tons of insects. Bats also eat plant pathogens.
While some species eat fruit, frogs and fish, only three percent of bats
feed on blood. They have good vision and extraordinary navigational
The fungus first seen in New York
and has spread as far south as Tennessee.
It appears to spread from bat to bat, sometimes killing up to 90
percent of a hibernating bat colony.The fungus is not known to harm
humans and humans may be spreading it.When bats and other creatures
hibernate in winter months their body temperatures drop and they tend to
suppress their immune systems. In 2008 researchers discovered WNS was
caused by an unusual Geomyces fungi,
that likes cold and has been found in Antarctica. It's not clear
howthe fungus is killing the bats. Professor Reeder explains the
growth on their skin may be an irritant that wakes them inappropriately
during hibernation, burning their stored body fat and inducing them
into winter flights in futile search of food, and ultimately leading to
their exhaustion and starvation.
It's maladaptive for a
pathogen to kill its host, Professor Reeder says, so when a new pathogen
moves into anew area, the result is a natural selection survival race
between the fungus and the bats. She sees some hope for bat survival
because bats afflicted with the fungus in Europe, where the pathogen
seems to be older,have not died
"Bats have gotten bad press," Kunz observes. In Western culture, we tend to fear things that come out at night. In Chinese culture, bats are considered good luck
Professors Reeder and Kunz say citizen scientists can help improve
understanding of bats and WNS by reporting discoveries of sick or dying
bats, or disoriented bats flying in daylight. The US Geological Survey
has an excellent web page on WNS and bats. The US Fish and Wildlife Service tells how you can help.
Listen to the NPR broadcast here.