Influence of intraspecific competition and habitat quality on diurnal activity budgets of breeding common goldeneyes

Abstract

We examined how female common goldeneyes (Bucephala clangula) allocated time to various activities throughout the breeding cycle, and how time allocation was influenced by habitat quality (presence of fish competitors) and intraspecific competition. Before incubation and during incubation recesses, females spent 73% or more of observed time foraging, but brood defence became the dominant behaviour during brood-rearing (43%). Females preferentially used lakes with few or no fish at all stages of the breeding cycle. Females sharing lakes with other goldeneyes spent significantly more time alert, in social interactions, and diving for food, and less time resting than females occupying lakes solely with their mate. Our results show that the amount of time female goldeneyes spend in various activities may be determined primarily by their metabolic requirements at each stage of breeding, but that habitat quality and intraspecific competition also influence how females allocate their time.