Brad Plumer lets us know about White Nose Syndrome, which has killed something like a million bats in North America. Bats are being found dead with white fungus on their noses. One of the awesome things about bats is that they can eat thousands of mosquitos a night. On a good night, a bat can eat its weight in pesky flying insects. They also pollinate crops.
That picture (from Talke Photography on Flickr) is a bunch of bats flying out from under a large bridge in Austin, where they sleep during the daytime. I saw it once, and it was pretty amazing -- the bats kept on flying out like that for about half an hour. I was impressed by the sheer number of bats that the bridge could shelter.