Bat Count at the Barn

If you like bats, counting, or counting bats, this project may interest you. The Connecticut Department of Energy and Environmental Protection is coordinating with volunteers in order to perform bat colony emergence counts. These counts take place in the later evening and start exactly a half an hour before sunset. In order to do a successful bat count, the temperature can't be too cold and it can't be too windy. 

The goal of the counts is to approximate the size of bat roosts before and after the pups are able to fly. The process of counting the bats is actually very straightforward and simple to do. All you need is a couple of lawn or folding chairs, some bug spray (trust me. You don't want to forget this!) and a means to record the number of bats you see fly out of the roost. Our intern David and myself have already done one bat count at the green barn which yielded an average count of 130 Big Brown Bats. The process will be complete when we do another count after the pups are able to fly (sometime in July). 

The Big Brown Bat roosting area in the barn

The necessity to estimate bat colony size comes from the threat that is currently facing the bat populations of Connecticut: White Nose Syndrome (WNS). WNS is the name given to the disease that is killing off hibernating bats in eastern North America. It has already been documented in 26 states and in 5 Canadian provinces. The disease is named for the white-colored fungus (Pseudogymnoascus destructans) that can appear on the muzzles and wings of affected bats, though it doesn't have to be present in every case. 

Individuals affected by WNS can exhibit erratic behavior in and around their hibernacula (caves where bats hibernate for the winter). WNS causes the bats to become unnecessarily active in the winter, making them lose their fat reserves more quickly. As winter carries on, these bats end up dying off in large numbers. Thus, it's important for us to keep track bat populations to see which ones are at most risk. And because of the high mortality rates seen in other bat populations, being able to save reproducing pairs may be necessary in order to prevent a population collapse.