American Coot (Fulica Americana)
Merritt Island National Wildlife Refuge, Florida
More shots to show you what the coots were doing. In this shot, you can see how they were moving in close groups. In the next shot, you can see how they began to move through the alligator area - one at a time, running and churning up the water. When they decided to all move at once it was quite a racket. Hard to imagine that the noise was created by coots. I wish we could have stayed another day to observe their behavior and try to capture what was happening. Video would probably be the best way to capture their behavior. Of course, I had my big lens on during most of the activity and it tends to isolate the perspective instead of showing the entirety of the masses.
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American coots form flocks of all sizes from just a few birds to hundreds. On this particular day, the coots were gathering by what appeared to be thousands! I've never seen anything like it. I believe they were wanting to go out into the open water, but it required they pass through some channel areas. And of course, the channel areas had some alligators. The coots were backed up considerably, but they would run frantically over the water to reach their destination, and to simply catch up to the group. It was a perfect example of "protection in numbers."
While they may be shy or skittish during most of the year, these can be aggressive birds during the breeding season and males will use both their feet and bills to attack intruders, including other coots and waterfowl. When taking flight, they run along the surface of the water while flapping to gain enough speed for takeoff.
Often mistaken for a duck, the pond-swimming American coot is actually more closely related to rails and moorhens and is a popular resident on ponds and in similar marshy habitats throughout the United States.
Source: About.com