Effect of forest cover on ectoparasites of small mammals in the Brazilian Atlantic forest

Abstract

Habitat reduction is one of the greatest threats to biodiversity and one of its many expected consequences is the negative impacts on host species. In this study, we evaluated if the reduction in the forest cover positively affected the richness and abundance of ectoparasites and rates of parasitism on mammal species. The study was carried out in the Atlantic Forest biome in the state of Bahia between January to March and September to November of 2011. We sampled four areas with different amounts of forest cover (%) in the municipalities of Valença (25%), Nilo Peçanha (35%), Camamú (45%) and Jaguaripe (55%). We identified twenty species of ectoparasites (fleas, mites, ticks) on 130 small mammals from 18 species (14 rodents and four marsupials), and the most abundant ectoparasites were mites. We confirmed our main hypothesis: the greater richness and abundance of ectoparasites was associated with a reduction in forest cover, with possible epidemiological implications. The prevalence of ectoparasitism per area varied from 91% in Valença to 50% in Jaguaripe. The mean intensity of ectoparasites per host was 6.5 for Valença, 6.4 for Nilo Peçanha, 10.4 for Camamú and 3.2 for Jaguaripe. Ours findings confirm that the reduction in the amount of forested is related to amplified rates of parasitism and changes in ectoparasites abundance and species richness.