Biogeographic patterns of avian malaria parasites in the Lesser Antilles: Prevalence, diversity, and community composition.

We investigated determinants of local and regional species richness and community composition of avian malaria parasites (Haemoproteus and Plasmodium) in the Lesser Antilles. Chapter 1 addresses the local parasite richness and community structure, or lack thereof, on Barbados. We found only two parasite lineages on this island, one of which was recovered from only 2 birds, which stands in stark contrast to the much higher diversity on other islands. In addition, we investigated what factors may explain the absence of avian malaria in southeastern Barbados, and found this area to be drier, warmer, and supporting less vegetation. Chapter 2 addresses parasite diversity, primarily beta diversity, in the Lesser Antilles. In this chapter, we investigated the role of host history and compound communities in structuring local ensembles. We found that host genetic distance does not correlate with ensemble dissimilarity but that more phylogeographically structured host species exhibit more unique parasite ensembles compared to the compound community than do hosts that are not phylogeographically structured, suggesting that host history does influence parasite ensembles.;Keywords. Avian malaria, Haemoproteus coatneyi, environmental variation, beta diversity, island biogeography, Lesser Antilles.