Abstract

CALEGARO-MARQUES, Cláudia  and  AMATO, Suzana B.. Parasites as secret files of the trophic interactions of hosts: the case of the rufous-bellied thrush. Rev. Mex. Biodiv. [online]. 2010, vol.81, n.3, pp.801-811. ISSN 2007-8706.

Helminths with heteroxenous cycles provide clues for the trophic relationships of definitive hosts, representing important sources of information for assessing niche overlap between males and females of non-dimorphic species. We necropsied 151 rufous-bellied thrushes (Turdus rufiventris) captured in a metropolitan region in southern Brazil to analyze whether the structure of parasite communities is influenced by host sex or age. Most thrushes (93%) were parasitized by at least 1 species. The helminth community of Turdus rufiventris was composed of 15 species with prevalences from <1% to 60%. Although the prevalence of Conspicuum conspicuum, Microtetrameres pusilla and Aproctella stoddardi was higher in adults, Syngamus trachea was more prevalent in juveniles. Adults showed greater species richness of parasites than juveniles, probably as a consequence of an increase in the opportunities of infection with a larger set of parasites with aging. Adult males and females presented similar species richness of helminths and quite similar communities, allowing us to conclude that they prey upon the same invertebrates, including earthworms, snails, isopods, millipedes, cockroaches and grasshoppers. Therefore, trophic niche overlap between adult males and females is greater than between adults and juveniles.

Keywords : Turdus rufiventris; passeriform; helminth; diet; dimorphism.