By 1965, Anne LaBastille, the scientist and bird expert, knew more about the giant grebe, Podylimbus gigas. It is one of three species of flightless grebes, all confined to high-altitude lakes in Latin America. Its wings and flight muscles are too small to lift its large body off the ground for flight. It is highly successful as a diver, however—able to remain submerged for as long as 90 seconds.
Pairs of grebes claim and defend a territory requiring dense, wide reed beds along 300 feet or more of shoreline. This species builds a giant nest in the reeds, 18 inches wide on a base 36 inches deep. Other species of grebe typically build a more flimsy floating nest, also placed among the reeds for protection from wave action.
Both parents care for grebe chicks for their first three months. During that time the mortality is about 50 percent. As the grebes mature and go out on their own, their death rate increases. The chicks eat insects, crustaceans, and small fish, but the young black bass are so spiny that they are difficult to swallow.
Go to Historic Update III—"Why is the Grebe Population Dropping?"
Image Credit: Photograph of Atitlan Grebe Model provided by Taylor Studios, Inc., © 2000. All Rights Reserved. Used with permission.
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