Spatial consistency in susceptibility of prey species to predation by two Accipiter hawks

作者：Moller Anders Pape^*; Solonen Tapio; Byholm Patrik; Huhta Esa; Nielsen Jan Tottrup; Tornberg Risto

来源：Journal of Avian Biology, 2012, 43(5): 390-396.

DOI：10.1111/j.1600-048X.2012.05723.x

Predators impose strong selection on their prey, regulate prey populations and engage in coevolutionary interactions with their prey. The intensity of selection and the strength of coevolutionary interactions will depend on how stringent predators are in their choice of prey. We estimated susceptibility of different species of birds to predation by two common raptors, the northern goshawk Accipiter gentilis and the Eurasian sparrowhawk A. nisus, in an agricultural landscape in Denmark and boreal forests in Finland. We estimated susceptibility to predation as the deviation of the log10-transformed observed frequency of prey of different species from the log10-transformed expectation based on population density during the breeding season. We found a high degree of consistency in susceptibility to predation by the goshawk in two areas in Finland. More importantly, there was significant consistency in susceptibility to predation between Denmark and Finland, albeit the degree of consistency in the goshawk was higher than in the sparrowhawk. There was considerable overlap in susceptibility to predation between goshawk and sparrowhawk in Denmark, but not in Finland, implying differences in intensity of interspecific competition as reflected by a much higher extent of goshawk predation on sparrowhawks in Denmark than in Finland. Our findings suggest that hawks impose similar selection pressures on their prey populations, and that the degree of consistency has implications for intensity of interspecific killing.

• 出版日期2012-9