Midwest Fish & Wildlife Conference 2017

AUTHORS: Johanna Fornberg, Johannes Foufopoulos - University of Michigan

ABSTRACT: Native parasites can play an important role in wildlife communities, as population regulators and as competitors with their hosts. Understanding the dynamics and implications of native parasites and pathogens is necessary to predict effects of introduced disease in a wildlife community. Island populations are considered to be particularly susceptible to introduced disease; however the ecology and distribution of native diseases in island systems are underrepresented in current literature. We present research on host-parasite interactions in isolated populations of island-dwelling Podarcis erhardii with native malarial parasites (family Hepatozoon). Research was conducted across 23 Aegean islands in a land-bridge island system which vary in age (time of isolation) and area (km2). We analyzed the nature of host-parasite interactions by studying 1) how infection and parasitemia varies based on island characteristics; 2) how immune function varies across islands; and 3) how infection and parasitemia relate to physical condition of individuals. We study these questions using a combination of field and laboratory work; laboratory work is still ongoing through the end of the calendar year. We expect to find the following, based on our hypotheses: 1) infection and parasitemia will be lower in populations on islands which are smaller (km2) and/or have been isolated for a longer period; 2) immune function will correlate positively with infection and parasitemia (i.e. immune function will be weaker in populations on smaller islands and/or more isolated islands; 3) physical condition will be reduced (based on infection and parasitemia of individuals). This study will provide insight to the impacts of island biogeography on host-parasite evolution and interactions.