Exploitation of a seasonal resource by nonbreeding Plain and White-crownedpigeons: Implications for conservation of tropical dry forests

Columbids often exhibit irregular movement patterns in response to fruit ab undance. We tested whether the abundance of nonbreeding Plain (Columba inor nata) and White-crowned (C. leucocephala) pigeons was correlated with Thrin ax parviflora fruit production in a dry forest in southeastern Jamaica. Mon thly, 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 roos t count, we also counted all fruits on ten T. parviflora trees in the fores t. Columbid and fruit counts showed similar patterns of temporal abundance, with increases from November to January and decreases from January to Marc h. Peak (January) counts of White-crowned Pigeon, Plain Pigeon, and unident ified columbids were 129, 77, and 151, respectively. The peak Plain Pigeon count was approximately three times greater than the highest counts previou sly recorded for Jamaica. These data indicate that the Portland Ridge dry f orest may provide a critical resource for the Plain Pigeon, perhaps at a ti me when fruit abundance is low on other parts of the island. Given the glob ally significant number of Plain Pigeons that use this site, protection fro m further development should be a priority.