{"fact":"Crows sometimes visit their nests empty-beaked, not to feed chicks, but to clean the nest.","context":"We suggest that crows sometimes visit the nest with no food merely to carry out other nestling care activities, for example nest cleaning. This is consistent with the fact that empty visits were shown mainly by breeding females, who perform most of the nest cleaning.","source":"Daniela Canestrari; Jos'e M. Marcos; Vittorio Baglione, False feedings at the nests of carrion crows Corvus corone corone, 10.1007/s00265-003-0719-8","index":129}