EXPLOITATION OF A SEASONAL RESOURCE BY NONBREEDING PLAIN AND WHITE-CROWNED PIGEONS: IMPLICATIONS FOR CONSERVATION OF TROPICAL DRY FORESTS

Abstract

Columbids often exhibit irregular movement patterns in response to fruit abundance. We tested whether the abundance of nonbreeding Plain (Columba inornata) and White-crowned (C. leucocephala) pigeons was correlated with Thrinax parviflora fruit production in a dry forest in southeastern Jamaica. Monthly, from November to March, we counted the number of pigeons leaving the forest to roost in an adjacent mangrove swamp. Within two days of each roost count, we also counted all fruits on ten T. parviflora trees in the forest. Columbid and fruit counts showed similar patterns of temporal abundance, with increases from November to January and decreases from January to March. Peak (January) counts of White-crowned Pigeon, Plain Pigeon, and unidentified columbids were 129, 77, and 151, respectively. The peak Plain Pigeon count was approximately three times greater than the highest counts previously recorded for Jamaica. These data indicate that the Portland Ridge dry forest may provide a critical resource for the Plain Pigeon, perhaps at a time when fruit abundance is low on other parts of the island. Given the globally significant number of Plain Pigeons that use this site, protection from further development should be a priority.