Bird-dropping nuisance under power lines used as perching and roosting sites by crows Corvus

Abstract

We observed patterns in crows landings on an overhead power line in Utunomiya, Tochigi Prefecture, Japan, from November to December, 2018. The number of crows landing on the power line was highest in half an hour after sunset, then began to decrease for returning to their roost. In addition, since more than a hundred individuals keep staying on the power line in one hour after sunset, the power line may function not only as a pre-roosting assembly site, but also as a roosting site for crows. In addition, bird-dropping nuisance by the crows was observed under the power line.