The Mosque Swallow (Cecropis senegalensis, syn. Hirundo senegalensis) is a large swallow. It is a resident breeder in much of sub-Saharan Africa, although most common in the west. It does not migrate, but will follow the rains to some extent.
This is a bird of open country with trees, and cultivated areas. It builds a closed mud nest with a tubular entrance in a cavity or under bridges and similar structures. It will use deserted buildings, tree holes or caves. Three or four eggs is a typical clutch.
Mosque Swallow is like a giant Red-rumped Swallow, 25cm long, with blue upperparts other than a reddish collar and rump. The face and underparts are reddish, but the underwings are white with dark flight feathers. The tail is forked, and slightly longer in the male. Juveniles are duller and browner, with less contrast.
It can be distinguished from the similar Rufous-chested Swallow by the slightly larger size but shorter tail streamers. The dark crown extends below the eye in that species, but not in Mosque Swallow.
The flight is slow and heavy, and this and its large size can give a first impression of a falcon rather than a hirundine. These birds feed on insects caught in the air.