Helping endangered bats should not be this hard

Two weeks ago I was standing on Swinington Hill Road in Leicester at 10:00 PM watching bats fly through my flashlight beam. I had a bat detector so I could “hear” when a bat was approaching and then easily find it with the flashlight. At one point a moth flew through the beam and I was able to follow it until it dove downward as a bat swooped in and caught it a few feet above the tarmac. All the bats I saw in the flashlight beam were less than 20 feet above the road. I made 46 recordings of bat calls in 35 minutes, and later a call identification program told me that all four of Vermont’s endangered species of bat had been present. I am not convinced that all four of them were there. Those species have similar ultrasonic calls and the program cannot always distinguish them reliably. But most of them can usually be distinguished from Vermont’s other bats, so although I can’t be sure which species were present, I have some confidence that many of the bats I encountered that night were on Vermont’s endangered species list.

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Bat plus ultra

This summer there was a bat or two flying over the yard every evening, so I started lying in wait for them with a camera. For about 15 minutes at dusk there was enough light to capture a bat silhouette if I used a good DSLR at the highest ISO. The photos were fun, but you can’t tell what kind of bats they are from the photos. Someone suggested using a bat detector — an ultrasonic microphone that listens to the otherwise silent calls of bats and even suggests which species are calling.

Unidentified bat in pursuit of a dragonfly in my yard at 8:24 PM on August 8, 2020. Nikon D3100, Nikkor 1:2.5 105mm lens, 1/2000 second, f/2.5, ISO 12800 (Hi2).
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