Blue Swallow

The Blue Swallow, Hirundo atrocaerulea, is a small, resplendent member of the swallow family, measuring 18–25 centimeters in length. The adult's plumage is a striking dark metallic steel-blue, with a lustrous sheen that can appear almost black in dim light. Males are distinguished by their elongated tail streamers. When preening or engaging in courtship displays, white feathers on the rump and flanks become visible. Juveniles begin life in a more subdued brownish-grey, gradually acquiring the species' characteristic blue as they mature.

Identification Tips

In flight, the Blue Swallow can be identified by its "bee-bee-bee-bee" call, a musical note that carries through the air. The long tail streamers of the males are particularly distinctive. In less than ideal lighting conditions, one might confuse them with the black saw-wing swallows, Psalidoprocne spp., which share their range.

Habitat

The Blue Swallow favors montane grasslands with high rainfall and undulating terrain for breeding. During the winter months, it prefers open grasslands dotted with bushes and trees.

Distribution

This species breeds in the Afromontane regions stretching from South Africa to Tanzania and winters north of Lake Victoria.

Behaviour

Arriving at their breeding grounds at the end of September, Blue Swallows construct cup-shaped nests within sinkhole cavities, aardvark burrows, and old mine shafts, using mud and grass. The nests are lined with fine grass, animal hair, and white feathers. After breeding, they migrate to their over-wintering grounds in April.

Song & Calls

The Blue Swallow's call is a melodic "bee-bee-bee-bee" heard during flight.

Breeding

The breeding system of the Blue Swallow is not fully understood, though co-operative breeding is common. Typically, three white eggs are laid, incubated by the female for 14 days. Chicks are then fed for about 22 days until they fledge. Many will rear a second brood before migration.

Diet and Feeding

Blue Swallows feed on small, soft-bodied flies and other arthropods, which they catch adeptly on the wing.

Conservation status

The Blue Swallow is classified as Vulnerable, with habitat destruction posing a significant threat at both breeding and wintering sites. The current population is estimated at 1,500-4,000 individuals and is in decline.