House Martin Factfile
The House Martin is a summer migrant to the UK from its wintering grounds in Africa. It is a smallish bird with a glossy blue-black back and pure white underparts and distinct white rump. It has a forked tail but doesn’t have the long streamers that a swallow has – and the lack of these, along with the white rump, is the best way to tell the House Martin from a Swallow at a glance when in flight. For bird lovers it is a thrill and privilege to have House Martins build nests under the eaves of their house, but for non-bird-lovers it is, sadly, often anything but, with the mess the birds create often resulting in the destruction of nests – something which is illegal if the nest is being built or is in use.
House Martin nesting and breeding habits
The House Martin’s nest is a rounded half-cup which is constructed of mud and some plant material, then lined with feathers and soft grass. The nest takes the birds up to 10 days to build, and is located under the eaves of a house or other building, or, less commonly in the UK, under a ledge on a cliff face. Often existing nests from a previous season will be repaired and reused. Both sexes build the nest, incubate the eggs and feed the young. There are normally two broods per season with a clutch size of four to five eggs, though occasionally a third brood is attempted which may result in the young birds not leaving the nest until October. Some pairs will nest in isolation, with other forming colonies of up to 30 pairs. Artificial nest will also be used, and the provision of these can encourage a colony to form.
House Martin history and population trends
Overall, the population trend in the UK is one of slight decline and hence why the species is now listed as amber status. However, this decline has largely been from SE England, and in other parts of the UK – e.g. Northern Ireland and NE Scotland – there has actually been an increase in numbers.
Behaviour traits of House Martins
This is a highly entertaining species to watch, and be it building its nest to hunting flying insects as part of a large flock – which will often include Sand Martins and Swallows – in the very late summer. An especially interesting behaviour has been recorded, and this is that young from the first brood may help feed the young still in the nest on the second brood – and the third brood when this more occasionally takes place.
House Martin diet and food
The diet is entirely flying insects caught on the wing.