Red-rumped swallow

Appearance

Red-rumped swallows are somewhat similar in habits and appearance to the other aerial insectivores, such as the related swallows and the unrelated swifts. They have blue upperparts and dusky underparts.

They resemble barn swallows, but are darker below and have pale or reddish rumps, face and neck collar. They lack a breast band, but have black undertails. They are fast fliers and they swoop on insects while airborne. They have broad but pointed wings.

Distribution

The red-rumped swallow breeds across southern Europe and Asia east to southern Siberia and Japan, These populations, along with Moroccan birds, are migratory, wintering in sub-Saharan Africa or south Asia. There are resident races in Africa in a broad belt from West Africa east to Ethiopia and then south to Tanzania, and most Indian and Sri Lanka breeders are also year-round residents. The African and Asian subspecies may undertake local seasonal movements. This species is a regular vagrant outside its breeding range.

Status

The International Union for Conservation of Nature is the organisation responsible for assessing the conservation status of species. A species is assessed as subject to varying levels of threat if it has a small, fragmented or declining range, or if the total population is less than 10,000 mature individuals, or numbers have dropped by more than 10% in ten years or with a continuing decline generations. Red-rumped swallow has a huge range and a population numbered in millions. It is not known to be seriously declining in range or numbers, so it is classed as Least Concern.

The red-rumped swallow is extending its range northward in Europe, colonising France and Romania in recent decades. The European population is estimated as 100,000 to 430,000 breeding pairs or 300,000 to 1,290,000 individuals.

Behavior

These swallows are usually found over grassland where they hawk insects. They may sometimes take advantage of grass fires and grazing cattle that flush insects into the air.

Reproduction

Red-rumped swallows build quarter-sphere nests with a tunnel entrance lined with mud collected in their beaks, and lay 3 to 6 eggs. They normally nest under cliff overhangs in their mountain homes, but will readily adapt to buildings such as mosques and bridges.

They do not normally form large breeding colonies, but are gregarious outside the breeding season. Many hundreds can be seen at a time on the plains of India.

It is thought that the sequence "open-nest" to "closed nest" to "retort nest" represents the evolutionary development in the mud-building swallows, and individual species follow this order of construction. A retort builder like red-rumped swallow starts with an open cup, closes it, and then builds the entrance tunnel. It has been proposed that the development of closed nests reduced competition between males for copulations with the females. Since mating occurs inside the nest, the difficulty of access means other males are excluded. This reduction in competition permits the dense breeding colonies typical of the "Delichon" and "Petrochelidon" genera, but colonial breeding is not inevitable; most "Cecropis" species are solitary nesters.