Sand Martin (Riparia riparia) of Britain and Ireland
Sand Martins arrive in Britain and Ireland between March and April after flying 3,500 miles from their wintering grounds in Africa. They are fairly common and widespread birds which breed in sand and river banks along rivers and in the open countryside. They leave again for Africa between August and September.
Adults are the smallest of the Hirundine species to breed in the British Isles. They are about two thirds the size of their cousins, the House Martin and Swallow.
Sand Martins are sociable who breed in open country where water is nearby. They are common on farmland, pastures, rivers, quarries and wetlands. Urban areas, woods and mountains are generally avoided.
Pairs breed in colonies and make their nests in sandbanks and riverbanks.
The main diet of Sand Martins are insects such as flies, aphids, hoverflies, flying ants and midges which are caught in the air.
Sand Martins fly across the Sahara Desert in Africa and arrive in Britain and Ireland between mid-March and April.
A map of the breeding distribution of Sand Martins in Britain and Ireland has been supplied by the British Trust for Ornithology: https://app.bto.org/mapstore/StoreServlet?id=321 .
Flocks of Sand Martins leave for the wintering ground in Africa between late July to September. Most of the wintering population are thought to congregate around the Sahel.
The Sahel lies between “the Sahara to the north and the Sudanian Savanna to the south” (Wikipedia - https://en.wikipedia.org/wiki/Sahel ).
Sand Martins breed in colonies of up to 100 pairs. They make their nests in sandy, dry banks found sand pits, gravel pits, railway embankments, riverbanks and sea cliffs. Some pairs choose holes in walls, drainpipes and brickwork.
The nest is a chamber at the end of a long tunnel which can be up to a metre deep. Pairs excavate between 8 and 10 centimetres into the sand each day. They line the chamber with grass, leaves and feathers.
Four or five white eggs are laid in late May or early June and take 2 weeks to hatch. Both parents care for the young who learn to fly after 19 or 24 days. The young are dependent on their parents for another week.
Pairs often raise 2 broods a year if there is good weather in the summer. Some males and females seek another mate and start a new family.
(A short video on a colony of Sand Martins can be found on Birdguides: https://www.birdguides.com/species-guide/ioc/riparia-riparia/ ).
Adults and chicks are vulnerable to the American Mink and foxes.
The Sand Martin is classified as of Least Concern by IUCN.
There has been a slight decline in the population of Sand Martins in North America over the last 40 years. The population trend in Europe is unknown.
A map of the breeding sites of Sand Martins in Europe has also been provided by the BTO: http://s1.sovon.nl/ebcc/eoa/?species1=9810.
The Sand Martin is a green-listed species of bird in Britain. They were moved from the amber list to the green list of birds in 2015.
The Sand Martin is an amber-listed species of bird in the Republic of Ireland.
The BTO said the population suffered “steep” declines throughout the late 1990s and early 2000s. The latest figure suggested, “a stable or shallowly increasing population, with wide fluctuations”.
Sand Martins are difficult to monitor as “active and inactive nest holes are difficult to distinguish, and because whole colonies frequently disperse or shift to new locations as suitable sand cliffs are created and destroyed”.
The status of Sand Martins in Europe was described as “depleted”. (BTO – Trends: https://app.bto.org/birdtrends/species.jsp?&s=sanma ).
The Breeding Bird Survey said in 2018 “Winds from the north through much of the spring migration period could have taken their toll on migrant species returning to the UK from Africa, but conditions on wintering grounds could also have contributed to the year-on-year declines for some of the UK’s migrant species. House Martin (-17%), Sand Martin (-42%) and Swift (-20%) all declined between 2017 and 2018” (BBS – page 14 : https://www.bto.org/sites/default/files/bbs-report-2018.pdf ).
The population of Sand Martins occasionally “crashes” because of drought conditions in their wintering quarters in Africa. Their numbers are also affected by overgrazing by livestock, climate change, manmade changes made along rivers and in quarries and pesticides.
Netting placed near their breeding grounds can also cause problems for colonies (BBC - https://www.bbc.com/news/uk-england-norfolk-48838611 ).
For more information on the birds of the gardens and countryside of Britain and Ireland, please visit
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