Levels of genetic differentiation and gene flow between four populations of the Scaly-naped Pigeon, Patagioenas squamosa: implications for conservation.

Island-endemic columbid species are particularly vulnerable to environmental degradation, extreme climatic events, and interactions with exotic species. The situation might be even more critical in the case of exploited species, where legal hunting and poaching can severely affect population dynamics. Here we document for the first time the genetic structure of the Scaly-naped Pigeon, Patagioenas squamosa, a Caribbean-endemic columbid species of cynegetic interest, over a large part of its range. Using both mitochondrial DNA and nuclear markers (microsatellites), we investigated gene flow, genetic diversity, and genetic structure among four islands populations originating from Puerto-Rico, Guadeloupe, Martinique and Barbados. We found evidence for a significant genetic differentiation only between the Barbados and the three other populations, consistent with the fact that the Barbados population originated from a few captive individuals escaped from a rooftop aviary in Bridgetown about 100 years ago. Given the absence of genetic differentiation between Puerto Rico and the French Antilles, our results suggest that, apart from Barbados, the species may mainly consist of a single large, homogeneous population. We discuss the relevance of our findings in relation to management and conservation issues. [ABSTRACT FROM AUTHOR]