Tree sparrow

The tree sparrow (Passer montanus) is often regarded as the country cousin of the more familiar (and much more common) house sparrow. This is generally true throughout its European range, but in Asia it fulfils the house sparrow role of being closely associated with human habitation.

The tree sparrow is resident where the climate is mild, as in western Europe and the UK, but northern and eastern populations are migratory.

Within the United Kingdom, the tree sparrow is found in isolated pockets in England, southern Scotland and the eastern half of Northern Ireland, but is virtually absent from Wales, northern Scotland and south-west England. Its preferred habitat is open woodland, farmland with hedgerows, orchards, parks and quarries.


Appearance

The tree sparrow, at 14 centimetres (5.5 inches) in length, is slightly smaller than the house sparrow and of sleeker and neater build. It can be distinguished by its chestnut crown to the head, neat black bib and dark cheek markings. It has two white wing bars and a yellow-brown rump. The tree sparrow is otherwise brown above and lighter below. The bill is black in summer with a yellowish base in winter. Male and female tree sparrows look alike.


Habits

The tree sparrow is generally a shy bird, but it is loosely colonial when nesting and mixes with other species in winter, including house sparrows, finches, buntings and siskins. It is more agile in flight than the house sparrow and is generally more active, often being seen flitting about with its tail cocked.


Voice

The tree sparrow produces a “tek tek” call when in flight, and has a high-pitched and a fast “chip chip chip” at other times.


Breeding behaviour

Often as early as February, female tree sparrows can be observed fluttering their wings and uttering soft cries as they perch on tree branches. This is to entice males to their side.

Nests are built in tree hollows or crevices in walls and buildings. The tree sparrow is a species that will readily use nesting boxes. They will make use of nests and hollows created by other bird species, and have even been known to build a nest on top of that of another bird, with eggs or young already present.

Both partners participate in building the nest, which typically consists of straw, hair and feathers.

The clutch is normally of five or six eggs, which both parents incubate for up to 14 days, and they then feed the chicks for anything up to 18 days, after which they are ready to fly. The family will stay together for a further 10 to 14 days. The tree sparrow is a sedentary species, so the young are unlikely to move far from where they were hatched. The adult birds are likely to return to the same nesting site in later years.

A second or third brood is usually raised each season.


Food

In spring and early summer the main food is insects and their larvae, found in trees and on the ground. Insects are sometimes caught on the wing. At other times, seeds form a larger part of the diet, particular from grasses, cereals and herbs.


Conservation status

The tree sparrow has red status in the United Kingdom, due to its relatively small population and declines in the 1970s and 1980s which were probably due to changes in agricultural practices and the increased use of insecticides and herbicides. The numbers appear to be stabilising at present, with a partial recovery in some areas.

© John Welford