Abstract
Avian migration is one of the biggest mysteries in science. Every year, small birds migrate hundreds of kilometers to their wintering ground in autumn and in spring they migrate back to their breeding ground. Especially fascinating are young birds on their first migration who – despite no prior knowledge of their goal –master these journeys with amazing precision. To successfully migrate, they need to undergo extreme physiological adaptations to survive this journey. Blackcaps (Sylvia atricapilla) small songbirds that migrate individually at night show a variety of different migratory phenotypes across their breeding distribution. In Austria, they exhibit a so-called migratory divide. Austrian blackcap populations on either side of the divide show clearly different migratory directions, they migrate south east and south west. The migratory divide is the area inbetween, where both phenotypes breed and possibly interbreed. When the birds migrate, so do the parasites that infect them. Between the avian host and the avian malaria parasite, there is a two-way interaction; the parasite has an influence on the bird‟s condition and thereby on the success of the bird‟s migration. A change in environment due to avian migration has an influence on the parasite‟s reproductive cycle. In this study, I am investigating these interactions by looking at the communities of avian malaria parasites in blackcaps across a migratory divide. I want to answer the question: Do avian malaria communities differ in disparate migratory populations of the host? To address this question I am studying the haemosporidian infections in blackcaps across Austria by using a nested PCR-based molecular method in combination with Sanger sequencing. My results reveal an overall prevalence of 89.2% and a presence of all three haemosporidian parasite genera. I found a significant correlation between avian malaria infection and the elevation of the host‟s breeding ground, but could not find a link between differences in migratory phenotype and avian malaria infection.
