C03
C03
Effects of niche choice on host-parasite interactions of common buzzards
Nayden Chakarov & Oliver Krüger
Phenotypic manifestations of niche choice, conformance and construction can be striking, but their effects on the life histories of individuals can also be long-lasting and rather cryptic. The immediate environment and the larger surrounding habitat where an animal chooses to reproduce, as well as the proximity to conspecifics, can have important life-history consequences not only for the individual, but also for its offspring. This is especially true for long-lived organisms, which use the same territory repeatedly over many years and may become constrained by previous choices, such as birds of prey. Nest site choice and its trans-generational consequences lead to research questions that are central to the entire CRC: How is niche choice mediated by direct and apparent competition, whether and how niche choice is matched to the phenotype, and how this affects the individual, population-genetic and evolutionary interactions with parasites. Both long-term as well as individual-based data are crucial to detect such effects and assess their relative importance for individualised niches.
After previously illuminating the mechanisms and consequences of niche construction in birds of prey, this phase of the project will further examine the determinants of habitat and social niche choice and reveal the consequences for the transmission, heritability and virulence of host-parasite interactions. We will continue to focus on common buzzards (Buteo buteo) and their most common vector-transmitted blood parasites (Leucocytozoon buteonis). To achieve the aims of this phase, we will fit buzzard chicks with GPS-GSM transmitters and thereby collect fine-scale information about the timing of movements, the choice of habitats and social environment through different life stages until death or recruitment into the breeding population and subsequent breeding attempts. Through a cross-fostering experiment, we will disentangle genetic effects on habitat choice and parasite inheritance from imprinting and social transmission. By deploying cameras at the nest, we will collect data to test if niche choice and social and parental behaviours become adapted to the individual phenotype and infection status. By using high resolution molecular and cytometry techniques, we will elucidate how the degree of antagonism in the interactions between blood parasites and the immune system of buzzards depends on the niche choice of their parents. This project will hence significantly contribute to key questions of the CRC by extending and complementing a unique data set with field experiments and state-of-the-art high-resolution data and by thoroughly connecting individual life histories with the chosen and inherited niches.
Letter of support
Prof Dr Martin Wikelski offers this Letter of Support for Project C03.
