In stunning findings, New York area scientists believe that 90% of the local bat population that hibernates in the state’s caves and mines will be dead by the time the snow leaves the ground. While no one is exactly certain of the cause, many of the dead specimens appear underweight and some have white fungal infections. Others have been found to have pneumonia, although scientists believe that this and the fungal infections are secondary to a larger cause. But what possible cause could this be and what sorts of consequences does this have for our environment?
The three most populous bat species in these caves are little brown bats, Indiana bats (which are on the Environmental Protection Agency’s Endangered List), and small-footed bats. The bat die-off isn’t isolated to this year either. One cave profiled in the New York Times’ article on the matter was observed to contain 15,584 hybernating bats in 2005, 6,735 in 2007 and a paltry 1,500 this winter.
While more than ten laboratories race to explain this phenomenon so that it can be stopped, wildlife conservationists worry that many of the bat species will go extinct as a result. Bats are especially susceptible to population decline because they can fly such long distances, spreading disease among a global bat community. Additionally, female bats give birth to only one pup per year, making the replacement rate sub-optimal in the face of an epidemic.
While some scientists are studying body weight as a factor (bats with too little body fat cannot sustain hybernation, which requires a special kind of “brown fat” between the shoulder blades), other research focuses on recently introduced pesticides that could either poison bats or reduce their food sources.
The fungal disease and bat pneumonia are not transmittable to humans, but the human population will be amiss without bats. Bats consume many of the insects that are considered agricultural pests. A study in Texas found that cotton farmers owed a sixth of the value of their crops to the Brazilian free-tailed bats who ate cotton pests. Further, bats are essential to plant propagation – spreading seeds on the forest floor through excrement and rubbing against, then delivering the pollen of flowers. These aside, bats are beautiful, fascinating creatures with a rich mythology and dynamic social structure. The bat biologists interviewed by the Times spoke to great effect about the emotional loss of this disaster.
(See New York Times Article here)