Aridity and avian ectoparasites: who, how many, where?

Abstract

Veiga, J., Valera, F. 2020. Aridity and avian ectoparasites: who, how many and where? Ecosistemas 29(2):1986. https://doi.org/10.7818/ECOS.1986

Our knowledge of the ecology of parasitism and the factors influencing host-parasite interactions is different between habitats, being both scarcer in arid and semiarid areas than in more mesic habitats. Arid environments are characterized by the lack of water and frequently by high spatio-temporal heterogeneity in the distribution of essential resources. This work explores the ectoparasite community of European rollers (Coracias garrulus) breeding in nest-boxes during two years with marked differences in rainfall. We found a varied community of ectoparasites, with at least 7 well represented taxonomic groups in both years. Despite clear differences in a key factor as rainfall, neither the prevalence nor the intensity of infection of the most prevalent ectoparasites varied significantly between years. The study of the spatial distribution of two ectoparasites with different dependence on water (blackflies – Fam. Simuliidae - and sandflies – Subfam. Phlebotominae -) showed that both taxa were distributed randomly in the study area, although sandflies had moderate interannual consistency in parasitization of the same nests between years. Our results suggest that other resources apart from precipitation (nesting sites, tree cover) could be more important in determining the prevalence, intensity of infection and spatial distribution of these parasites. Arid zones offer a great opportunity to complete and expand the knowledge about the ecology of ectoparasites.