Night Shift For Nature: Monitoring Bats Along the Green River

by Mike Hensley

So the call came again. Santiago Martin, a partner at the U.S. Fish and Wildlife Service (USFWS), wanted to head out into the night to monitor bats near the Green River. Our partners from USFWS call from time to time for help in lining up good places for conducting this work. Sometimes I suggest one of the Conservancy’s nature preserves. Other times, I can line up a landowner willing to host us for the night.

I love getting these calls because regular folks like me can’t just head out to assess the condition of bats. You need special permits for that because some of these furry friends are listed under the federal Endangered Species Act.

Santiago Martin weighs a gray bat near Kentucky's Green River.
Santiago Martin weighs a gray bat near Kentucky’s Green River.

I also help with the actual work—setting up the netting equipment and collecting data when a bat is captured. The process is pretty straightforward. An hour or so before dusk, we arrive at the site and pick out a location for setting up nets – typically near a body of water or in the woods and brushy fields where bats like to feed. A wooded tunnel is an ideal spot. (Picture a 15 to 20-foot wide trail running along the edge of a river with a closed forest canopy above it.)

On this night, we set up at a property located along the Little Barren River, a few miles away from the confluence with the Green River. The property is actually owned by Chris Mason, one of our conservation colleagues at Kentucky’s Department of Fish and Wildlife Resources.

Once nets are set up and darkness arrives, we find a comfortable place to sit with the equipment and set a ten-minute timer. Then, every ten minutes we check the nets. Sometimes we have a bat; most times we don’t. If we find a bat, we carefully remove it and return to the sit-down location to collect the data: measurements, gender and species. Then we release the bat back to the wild. We continue to do this every ten minutes for at least four or five hours before calling it a night.

Measuring a bat captured for study near Kentucky's Green River.
Measuring a bat captured for study near Kentucky’s Green River.

At one point in the night the Kentucky Chapter’s Director of Conservation Programs, Jeff Sole, and our new State Director David Phemister, paid us a visit. They must have been good luck because we found a gray bat in the net soon after their arrival! By the end of the night, we caught, studied and released (in order captured) a gray bat, two red bats, a little brown bat and a second gray bat.

A scientist handles a Gray bat captured near Kentucky's Green River.
A scientist handles a Gray bat captured near Kentucky’s Green River.

It’s a treat to help with this work once or twice each summer. One of the best parts of this type of work is meeting and working with really dedicated and skilled people and Santiago fit the bill. As a whole, the bats aren’t doing so well, so this work is very important to understanding the Green River habitat these bats depend upon for survival. Collecting as much information as we can will guide efforts to improve the situation for bats.