House Martins are a summer visitor.
They have metallic blue-black upperparts, white underparts and rump. The wings are broad, short and pointed and the tail is forked, but lacks the streamers of the Swallow. Both the wings and tail are brownish-black. Their tiny legs and feet are covered in white feathers.
Juveniles have brown crowns and the white areas are a buff-grey.
They are most easily confused with Sand Martins, but these are smaller, brown and lack the white rump.
In flight, House Martins appear black and white, with the white rump being a key characteristic. Sand Martins appear paler, lack the white rump and have a breast band. Swallows are larger than either martin and have long tail streamers as well as the red throat. Swifts appear black and it is the slim tapering body and scythe-like wings that are key identification features.
| Scientific Name | Delichon urbicum |
| Length | 12-15 cm (5-6") |
| Wing Span | 25-29 cm (10-12") |
| Weight | 15-20 g (½-¾ oz) |
| Breeding Pairs | 375 000 |
| Present | Summer |
| Status | Red |
Their song, which is sung either in flight or from a perch, is a twittering that carries on all summer.
The call is a weak chirrup.
House Martins feed on the wing; the diet is insects, such as flies, beetles and aphids.
They can sometimes be enticed in to our gardens by providing muddy patches from which they can collect mud for their nests.
They nest in colonies, building mud cups under the eaves of houses. The nests are frequently used for several years, often by the same adult birds or juveniles. Generally, they avoid urban areas, preferring to nest near houses and cliffs in more open habitats or near lakes.
Artificial nests can be purchased from some bird food suppliers.
The eggs are white, smooth and non-glossy, and about 19 mm by 14 mm. The male and female take turns incubating the eggs, and both adults feed the young.
| Breeding Starts | Clutches | Eggs | Incubation (days) | Fledge (days) |
|---|---|---|---|---|
| April-May | 2-3 | 2-6 | 13-19 | 19-25 |
House Martins are summer visitors, typically from mid-April until October. They winter in tropical Africa.
There is evidence to suggest that the population has declined by 25-50% but it is a difficult species to monitor and so obtain conclusive data. The declines may be localised and a number of causes have been aired: loss of livestock and muddy puddles, destruction of nests by ignorant or negligent property owners and shortening of their breeding season (they are arriving later and departing earlier), difficulties on their wintering grounds and harsh weather during migration.
