Identification

Carrion crows are large birds of the Corvid family that includes jackdaws, rooks, and magpies. They have glossy black plumage, often with a slight green or purple sheen. They have heavyset black bills, slightly curved at the end. As territorial birds they will usually be seen alone or in pairs. Non-breeding birds may form small flocks, and large communal roosts may form in the winter. They have a harsh, croaky call.

Until 2002, the grey-bodied hooded crows were regarded as a subspecies of the carrion crow, Corvus corone. However, they have since been classified as a separate species (Corvus cornix) in their own right. In parts of Scotland (roughly between Aberdeen and Glasgow) carrion and hooded crows interbreed to form hybrids of intermediate colour.

Size

44-52cm (17-21in) long, with a wingspan of 84-100cm (33 ½-39in).

Distribution

Carrion crows can be found throughout the UK, except for north west Scotland and Northern Ireland, where they are replaced by the hooded crow. Globally there are two separate populations, one in western Europe, and another in Asia. There is some debate as to whether these two populations constitute separate species.

Status

These are common birds and not considered to be threatened. The only real threat to populations is from persecution by those rearing sheep or gamebirds. Crows can steal eggs and may occasionally kill lambs or trapped sheep, however they are not as big a threat to livestock as is often perceived. It is not believed that this persecution has led to any widespread population decline.

Habitat preference

Carrion crows can be found in almost every UK habitat, from city centres to remote coastal areas.

Where to find them in the garden

Often seen in the tops of trees or on similar vantage points, surveying the garden for potential sources of food.

Role in the garden

Carrion crows feed on a range of foods, including dead animals, small mammals, birds, invertebrates and sometimes plant matter. They may be considered a pest by some, as they often feed on the eggs and chicks of other birds. However this is all part of the garden ecosystem, whereby predators such as crows help regulate populations of other species. These predator-prey relationships ensure that only the most able birds survive to adulthood, improving the survival prospects of the species as a whole. Problems only occur when external influences such as human interference create population declines, as has been seen in many of our small bird species. These declines may then be made worse by predation.