Common House Martin, avión común

Description:

It feeds on insects which are caught in flight, and it migrates to climates where flying insects are plentiful. It has a blue head and upperparts, white rump and pure white underparts, and is found in both open country and near human habitation. It builds a closed cup nest from mud pellets under eaves or similar locations on buildings usually in colonies, but sometimes fouling below nests can be a problem.

Habitat:

The preferred habitat of the Common House Martin is open country with low vegetation, such as pasture, meadows and farmland, and preferably near water, although it is also found in mountains up to at least 2,200 metres altitude. It is much more urban than the Barn Swallow, and will nest even in city centres if the air is clean enough. Under the house leaves in the Sierra de Guadarrama