RELATIONSHIP OF BILL MORPHOLOGY TO GROOMING BEHAVIOR IN BIRDS

Efficient preening by birds is critical for feather care and defence against harmful ectoparasites, yet many species have long, unwieldy bills that are presumably less efficient for preening than short bills. Long-billed taxa such as hummingbirds and toucans could attempt to compensate for inefficient preening by spending relatively more grooming time scratching with their feet than do short-billed taxa. To test this simple hypothesis preliminary data on the grooming behaviour of wild birds in Costa Rica and more extensive data on captive birds in zoos were collected. Comparative analyses of these data support the hypothesis and suggest additional hypotheses for future testing. © 1993 The Association for the Study of Animal Behaviour.