EXAMPLES OF TROPICAL FRUGIVORES DEFENDING FRUIT-BEARING PLANTS

In the tropics, birds have not been shown to defend fruit-bearing trees or vines, even though tropical birds defend other sources of food at high density, particularly flowers. Foraging of frugivorous birds in New Guinea was studied and 4 examples of feeding territories at fruiting woody plants described. A female blue bird of paradise (Paradisaea rudolphi) at Schefflera pachystyla, a male Indian koel (Eudynamis scolopacea) at Chisocheton sp., a male cinnamon-breasted wattlebird (Melidectes torquatus) at Dendrocnide ternatensis and a Reinwardt''s long-tailed pigeon (Reinwardtoena reinwardtsi) at S. chaetorrhachis. The birds of paradise, wattlebird and pigeon were individually recognizable. All 4 holders of feeding territories (defenders) attempted to chase away all other visiting birds (visitors) and succeeded, except in the case of the wattlebird, where some visitors were larger than it was. Chases were not always followed by feeding. Defenders either spent long periods at their feeding territories or visited them repeatedly. They held their feeding territories over several days.