Alpine Swift (Apus melba)

[order] APODIFORMES | [family] Apodidae | [latin] Apus melba | [UK] Alpine Swift | [FR] Martinet alpin | [DE] Alpensegler | [ES] Vencejo real | [NL] Alpengierzwaluw

Subspecies

Physical charateristics

Large, robust swift differing from all other fork-tailed west Palearctic swifts in underpart pattern. Plumage mainly umber-brown, distinctly paler above than all Apus except Pallid Swift, sharply relieved below by brown breast-band and white central underbody and throat.

Listen to the sound of Alpine Swift

[audio:http://www.aviflevoland.nl/sounddb/A/Alpine Swift.mp3]

Copyright remark: Most sounds derived from xeno-canto

Range

Eurasia, Africa : widespread, also India

Habitat

Birds cover an estimated 600-1000 km daily just flying, nature of terrain underlying this aerial habitat apparently only significant in so far as it affects pattern of air currents and abundance of flying insects. At lower levels the species usually avoids areas with frequent obstructions such as trees and buildings. Breeds in mountain rock ledges, crevices, caves, coastal cliffs, and occasional holes in trees. In recent years also found in tall buildings which has enabled extension of range over lowlands and northwards.

Reproduction

The Alpine Swift rears its young in a cup-shaped nest. This nest is usually built of feathers, fibers, sticks, plant down, and moss. The swift’s saliva is used as the glue that holds the nest together. The nest is usually glued to the vertical surfaces of rock cracks and the eaves of houses, with the saliva once again serving as the glue. The swift will lay a single clutch of one to four eggs, though three is the usual number. Both parents incubate the eggs for eighteen to thirty-three days. The nestlings are hatched naked, and they are reared for another six to ten weeks, not leaving the nest until they have acquired adult plumage.

Feeding habits

Flying insects and spiders of moderate size. Prey caught entirely in flight.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Migration

The nominate race, tuneti, nubifuga and S African populations of africanus are migratory. Migration occurs at high altitude and movements often only observed when poor weather forces birds groundwards. Migration from Palearctic on broad front, without noticeable concentrations at natural landbridges. Scarcity of records from W Africa suggests that trans-Saharan migration is preferred avoid Atlantic coast. Migration from breeding range occurs primarily September to mid-October, with many juvenils moving earlier in August. Main migration through Belan Pass, S Turkey, October-November, where it occurs in smaller flocks than Common Swift (79) and mainly in single-species groups (Sutherland & Brooks 1981). At the Bosporus migratory picture unclear as large Istanbul population embarks on early-morning feeding movements, but peak autumn passage early September (Porter 1983). Autumn passage late May to mid-December, peaking September-October, spring passage mid-January to mid-June, peaking mid-February to late March, Israel (Shirihai 1996). Huge migration noted over the West Bank in mid-March 1987 when during a 15-minute period 10,000 birds flew north only 50-100m above ground (Meininger & Bijlsma 1988). Present in Africa wintering grounds from October to March. Migratory populations of southern Africa leave the breeding grounds from May-August. Migration through Zimbabwe is noted March-June and August-October, Malawi March-April and August-October and probably Botswana April and September (Brooke 1997). First returnees appear in Mediterranean basin from second half of February, abundant from March in north-west Africa. In Switzerland arrives late March to early April, with some migration still apparent until mid-May. Resident populations of Africa are to some extent dispersive in the non-breeding season. In Natal undergoes altitudinal migration from 1,500-2,400 m to below 900 m (Johnson & Maclean 1994). The situation within India is particularly confused, with populations resident, though local migrations occur particularly in the monsoon. The race nubifuga from the Himalayas, is thought to winter in central India. (Chantler Phil Griessens G 2000)

Distribution map