Molecular characterization of Haemosporidians in different species of Sardinian breeding birds.. Haemosporidian diversity in Sardinian breeding birds.

Islands represent an interesting model for studies of host-parasite associations. Since islands can harbor endemic taxa, the presence of locally restricted parasites can not only be predicted, but insular parasite communities may show a higher level of diversity as compared to non-insular areas. Sardinia is the second-largest island in the Mediterranean Sea, hosts a diverse breeding bird community to include sedentary species, and serves as a migratory stopover point for birds that breed across Eurasia and winter in Africa. In the first assessment of an insular Mediterranean avian haemosporidian community, we examined the presence of haemosporidian blood parasites (Leucocytozoon, Plasmodium, and Haemoproteus) by amplifying their mtDNA cytb gene, which was sampled from birds, at seven ecologically diverse sites on Sardinia. The prevalence of infected birds was 55.3%, with a decrease from lower to higher elevations, and a higher prevalence was recovered in sedentary bird species as compared to short-distance and long-distance migrants. We recovered 116 haemosporidian haplotypes, of which 84 were novel. While a high number of novel lineages were recovered, the phylogenetic analysis did not recover Sardinia-specific clades; instead, some Sardinian lineages were more closely related to haemosporidian lineages previously recovered from continental Europe. Host-parasite network analysis recovered an intermediate value of the network level specificity index (H2′= 0.543), indicating a non-specialized host-parasite community. Across recovered haplotypes, 11.2% were species-specific, with some bird species showing high levels of haemosporidian prevalence.