I want to know if there’s any good way to tell the difference between a bird and a bat under low light conditions, and when the creature is flying around so crazily that you can’t get a good look at it.
Here’s the situation: I was sitting on my lakeside dock (in Tampa, FL) at sunset, around 8:45 pm. Six or seven small dark flying creatures appeared. They were the size of small birds. Their flight was erratic, zig-zagging, diving, almost instantaneously reversing direction, never in a staight line. Obviously they were pursuing a dinner of flying insects. Their wings were beating so fast that I couldn’t get a good look at their shape, and they never stopped beating; they never soared. They were also totally silent. I assumed they were birds, but when one of them swooped by quite close to me I thought it looked more like a bat.
For the last two days I have been outside from 8:45 to 9:00 observing these creatures (they only appear for 15 minutes or so) and I have not been able to form a definite opinion as to whether they are birds or bats. If anyone has any good way to tell the difference, such as by their flying characteristics, please let me know.