Birds: House Martin (Gabhlán binne), Delichon urbica

Often confused with its close relative the swallow, the House Martin is the bird that builds its cup-shaped mud nest under the eaves of houses in towns and villages all over Ireland. Strictly summer visitors, they start to arrive in April and depart again by October; it is known that they winter in sub-Saharan Africa, but, amazingly, the exact location of their main wintering grounds is still unknown.

Slightly smaller than swallows, the best way to identify a House Martin is by the prominent white patch on their lower back. Apart from this, the upperparts are entirely glossy blackish-blue and the chin, breast and belly are completely white: they lack the swallow's red face and dark breast-band. Like the swallow, the tail is forked, though without long streamers.

Particularly aerial birds, House Martins feed almost exclusively on flying insects. They can frequently be seen perched on electricity wires, but usually just come to ground when collecting mouthfuls of mud with which to build their nests: they mix the mud with saliva to form individual fast-drying little bricks.

Though some still nest on cliffs, the vast majority of House Martins now rely on buildings as nest sites. The biggest threat to them is the unwarranted and illegal destruction of their nests by thousands of Irish home owners each year. If you are lucky enough to have these birds nesting on your house, please tolerate them. Though they can be a bit messy, this is easily cleaned and they cause no damage nor pose any health risks.

NIALL HATCH

A free factsheet on House Martins is available for download from the 'Learn About Birds' section of the BirdWatch Ireland website www.birdwatchireland.ie or by calling 01 2819878. Village readers can also receive a free series of wallcharts all about birds around our homes by writing to: The Village Bird Chart Offer, BirdWatch Ireland, PO Box 12, Greystones, Co Wicklow.