Bad Business for the Bats

Post contributed by Mary, Conservation Corps Youth Outdoors crew member:


Photo: http://www.wildlife.state.nh.us/Wildlife/Nongame/bats/wns.html

As night time temperatures drop below 50 degrees, it is time for bats to hibernate. With hibernation, however, comes a new danger – White-nose syndrome (WNS). WNS is a bat disease that has been rapidly spreading across the United States and Canada. It is a skin infection caused by a fungus, Pseudogymnoascus destructans, which develops over the bats wings, ears and muzzles during hibernation restricting their breathing. This causes the bats to awaken from their deep hibernation sleep, which in turn causes them to rapidly deplete their fat stores before winter’s end resulting in death from starvation. Some bats appear to die directly from the infection as well, so the exact cause of this rapid death is still unclear. WNS, which is thought to have been brought from Europe to a cave in New York eight years ago, has spread to 25 states and five Canadian provinces decimating bat populations. If WNS infects a cave it can wipe out over 90% of the bat population. Bat populations cannot recover quickly from losses such as this because bats usually lead long lives and have only one pup a year.

Photo: U.S. Fish and Wildlife Service via flickr

There are seven species of bats in Minnesota, four of which hibernate as opposed to migrate and are therefore susceptible to WNS. All four of these species, Little Brown Myotis, Northern Long-Eared Myotis, Tri-Color Bat, and Big Brown bat, have been affected by the disease in eastern states. The fungus associated with WNS has been found in two Minnesota caves, Mystery cave and the Soudan mine, but so far bat populations have remained healthy. We hope the 2014/2015 winter will bring the same results because bats are essential to Minnesota’s ecosystems and agriculture and their disappearance could be detrimental. Bats are one of the only predators of night flying insects and consume them in huge numbers. A female caring for her young can eat her weight in insects in one night. Bats help keep down numbers of insect pests who can damage crops, prairies and forests, and not to mention are a nuisance to humans.

We can all help slow the spread of WNS by reporting to the Minnesota DNR any bats that you see flying during the day in the winter; a sign that they have woken up from hibernation and may be looking for food. It is also a good idea to not enter any caves where bats are hibernating as not to disturb them or possibly spread the disease which is thought to enter caves on the shoes and gear of spelunkers. If you do go in a cave make sure to wash your clothes, gear and shoes before and after entering. 

Want to know more?

http://www.dnr.state.mn.us/mammals/bats.html

http://files.dnr.state.mn.us/eco/mcbs/wns/wns_mn_bats.pdf

http://www.nwhc.usgs.gov/disease_information/white-nose_syndrome/

file:///C:/Users/Corps/Downloads/Coming_Crisis_for_Our_Bats_A.pdf