Sand Martin

• GeneralIt digs burrows up to 1 m into sandy banks to breed in colonies.
• Its scientific name comes from the Latin ripa, riverbank; in the Americas it is called the bank swallow.
• The chicks gather in crèches during the day and at night may sleep in neighbouring burrows: the parents recognise their own by individual calls.
• It prefers banks subject to natural erosion, such as river meanders; if the bank is stable it is forced to reuse the same burrows year after year, which harms the brood.
• It is the first migratory bird to reach Europe in spring, even before the swallows. It digs its own nesting burrows in earth banks or soft sandstone along riverbanks, and the texture of the soil governs the shape of the tunnel.

Skeleton type

Vertebrate - internal bony skeleton (bird)

Habitat & environment

Sandy river banks and gravel pits

Sexual maturity

12 months

Gestation / incubation

About 14-15 days, with both parents incubating

Litter / clutch size

4-5 white eggs, with two clutches a year from March on. Both sexes dig a tunnel of 50 to 100 cm into clay or sandy banks, ending in a breeding chamber lined with feathers and fine plant matter. The chicks fledge at 20 days and become independent at a month

Sources consulted: IUCN Red List; SEO/BirdLife (ficha y III Atlas: Fernández-García y Ruiz de Azua 2022); Gobierno del Principado de Asturias (Plan de Manejo, BOPA 188); Heneberg, Ibis 145; Herrero y García 2005, Locustella 3; Naturaleza Para Todos; Birding Málaga; Linnaeus 1758; Forster 1817

Best time: From March to September; it is the first migratory bird to reach Europe in spring, even before the swallows