The effect of hooded crows on hill sheep farming in Argyll, Scotland. The food supply of hooded crows.
Hooded crows (Corvus cornix) in Argyll, Scotland could be divided into 2 groups, one of which held territories in which they bred in summer and the rest which did not hold territories or breed and which lived in loose flocks throughout the year. During the winter large numbers of immigrant crows entered the area and joined the flocks. The crows took a very wide range of foods. In the lowland areas they fed chiefly on cattle feed during winter and insects in summer. In high ground areas they fed on carrion with some cattle feed in the winter and on insects in summer. Fat and protein conditions of the crows through the year showed that some of those living in the loose flocks were unable to find sufficient food during the winter and some died from starvation. Crows holding territories probably had sufficient food throughout the year.