PIERSMA T & EERDEN MR VAN (1989) Current research: Why Grebes eat feathers: the polish clot hypothesis. LIMOSA 62 (1): 51-52.

Great Crested Grebe Podiceps cristatus Grebes are different from other birds. So they are the only large numbers of birds that eat their own body feathers. ret begins as a grebes-chick, just hatched updated, the first master spring and will be offered The grebes are so habit-start it. The French naturalist yond Buffon (in 1781) the spring- grebes eating a strange phenomenon, he thought the birds were wrong, that floating feathers worn for fish. In 1926 and 1931 published Madon, a compatriot of Buffon, two long articles about eating feathers by grebes, under the significant Titles Ret problem of Grebe and Secret of Ret Loon . Madon came with a long series of possible explanations for spring-eterij. The best are: (1) eaten springs increase the amount of air in the stomach and thereby reducing the density, making it the Grebes easier to get from the water on the nest jump

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