Urban development reduces fledging success of Barn Owls in British Columbia, Canada

[摘要] ABSTRACT The decline of Barn Owls (Tyto alba) in Europe and North America has been attributed to the loss and fragmentation of grassland foraging habitat and increased urbanization; both factors can reduce reproductive output and adult survival. We examined how the composition of the agricultural landscape influenced fledging success (defined as the number of young fledged per nesting attempt) of a threatened population of Barn Owls in the Fraser Valley, British Columbia, Canada. Among landscape variables, only amount of urban cover was correlated with fledging success of Barn Owls: Fledging success decreased with increasing urban cover within a 1-km radius of the nest site. This effect was driven by increased brood reduction: Individuals at sites with more urban cover fledged fewer young but did not lay smaller clutches or fledge young in poorer condition. Given that brood reduction is linked to food availability in Barn Owls and other species, this suggests that food availability was reduced in more urb...

[学科分类] 动物科学

[关键词] agricultural landscape;breeding success;diet quality;Tyto alba;urbanization