Length: 12 – 13 cm
Wingspan: 26 – 29 cm
Weight: 11 – 20 g
Sand martins are small brown and white swallows. Adults have brown to grey upperparts, with pale-tipped feathers. Their upperwings, tails and flight feathers are dark brown with an iridescent green sheen.
Sand martins’ underparts are white with a brown breast band which can extend down the centre of the belly. They have short legs and feet which are dark brown or black and the bill and eyes are dark brown.
The breast band on juvenile sand martins is less conspicuous and their chins and necks area reddish-brown. Their bills and legs are browner than adult sand martins.
Sand martins breed in colonies of up to 1000 pairs. Males begin the build of a burrow until he finds a mate and then both sexes will complete it. They dig the burrows in sand or gravel on river banks, lakes and streams as well as cliff faces or sand dunes.
Sand martins lay 4-5 white eggs and both male and female share the incubation for 14-15 days. Both parents feed the chicks and they fledge 19-22 days after hatching but are fed for a further 5 days.
Sand martins eat on the wing catching insects and spiders taken from the ground or surface of water.
Where to see them
Sand martins arrive in the UK in April and return in October. They can be seen along rivers and lakes across the country as well as manmade gravel pits.
Did you know?
The sand martin is known as the bank swallow in North America and the collared sand martin in the Indian Subcontinent.