I don’t do links often on this website, but this one, the Bracken Webcam, bears linking to:
http://batcon.org/index.php/get-involved/visit-a-bat-location/bracken-bat-cave/bracken-webcam.html
Bat Conservation International stewards the Bracken cave, where during warm months the largest concentration of mammals in North America – twenty million Mexican-free tail bats – emerge from the cave every evening in search of an evening meal of mosquitoes, moths, and other insects, ranging more than one hundred miles at time.
Between the overwhelming smell of bat guano, the sight of thousands of creatures swirling out of the cave, observed and coveted by snakes and raptors, may be the most miraculous event in nature I’ve ever witnessed.
The cave is a few miles from Interstate 35 north of San Antonio almost next door to the Natural Bridge Caverns and is in real danger of being encroached upon or wholly engulfed by housing subdivisions.
It’ll be interesting to see how that “progress” vs. miracle of nature battle plays out.