About Hirundo dimidiata Sundevall, 1850
The pearl-breasted swallow, Hirundo dimidiata Sundevall, 1850, measures 13–14 cm in length. It has glossy blue upperparts and grey-white underparts. Its upper wings, underwing flight feathers, and forked tail are blackish-blue, while its underwing coverts are a darker shade of grey-white. Unlike similar species in the Hirundo genus, it has no white coloration in its tail. Males have slightly longer outer tail feathers than females. Juvenile pearl-breasted swallows are duller and browner than adults, and also have shorter outer tail feathers. The recognized northern subspecies, H. d. marwitzi, is darker and smaller than the nominate subspecies H. d. dimidiata, but these differences are small, and the species may actually be monotypic. The pearl-breasted swallow breeds in southern Africa, ranging from Angola, southern Congo, and Tanzania southward. It has a sparse overall distribution, but can be locally common in some areas. It is partially migratory; many birds that breed in the southwest of South Africa winter further north. This species inhabits dry scrub, farmland, and clearings, and is often found around areas of human habitation.
