Best time to see: mid Apr to mid Oct

Key facts

Black-and-white swallow-like bird, often nesting under the eaves of buildings

Habitat: towns, usually near water to provide mud for nests

Widespread and common summer visitor, but declining in Essex

Recognition

Compact swallow-like bird with white rump; 12–13 cm

Aerial bird often seen feeding over fresh water

Feeds on insects, flying higher than swallows but lower than swifts

Lifecycle

Nest is a dome of mud under eaves and/or on a vertical wall; usually in colonies

2–3 clutches of 4–5 eggs, May to August

Most arrive late, in May, and sometimes leave late, in October or even November, to winter in south and tropical Africa