Adapted from Jim Conrad's online book A Birding Trip through Mexico, This excerpt from "Laguna Catemaco" southern coastal Veracruz state
Toward noon the lake becomes a broad, shallow saucer of placid, shining quicksilver. The thousands of coots that earlier were dispersed across the lake's surface have gradually coagulated into groups closer to shore and as time passes the gatherings condense until finally they form tight knots keeping in sheltered bays. Having them closer at hand I'm astonished at how much they eat -- swallowing entire sprigs of an aquatic plant similar to the Elodea grown in home aquaria.
One coot latches onto a six-inch sprig too large to swallow and, although all the coots in that group float in a morass of the plant, a neighboring coot covets the large prize and rushes to rob it from the owner. A small contest erupts, drawing attention of other coots, who rush to join the fray. In the end the sprig breaks into several segments and no coot gets more than a modest snack.