The Crows: A Study of the Corvids of Europe

acorns action adult aggressive Alpine chough ants April attack autumn Azure-winged magpie behaviour bill Bird Study breeding British Birds brood brown captive carrion crows carrion/hooded crows cawing cent cliffs clutch colour communal roost Compare figs Coombs copulation Cornwall corvids Corvus cuckoo daurian jackdaws defence described display eggs Europe feeding female pre-copulatory flock birds fluffed Goodwin grey ground gulls Gwinner hatched head Holyoak hooded crow incubation intruder juvenile leave the nest less Lockie male March mobbing moult movements nest building nesting season nestling nictitating membrane non-breeders nutcracker observed pair formation parasites parents passerines pecking perch perhaps plumage predators preening primaries probably pursuit flights range ravens recorded red kites Red-billed chough rookery rooks rooks and jackdaws Scotland seeds seen sexes Siberian jay sometimes species spotted cuckoo Swanberg territory holders trees twigs usually wing and tail winter young birds