Avión Nepalí

Identificación

The adult Nepal house martin is 13 cm (5.1 in) long, mainly blue-black above and white below. It has a contrasting pure white rump, the tail and upperwings are brownish-black, and the underwings are grey-brown. The legs and feet are brownish-pink and covered with white feathers, the eyes are brown, and the bill is black. The chin is black but the extent varies clinally. In the northeast of the range, birds of the race D. n. cuttingi have black on the whole of the throat and the uppermost breast, but further west or south the black increasingly becomes restricted to the chin. There are no differences in appearance between the sexes, but the juvenile bird is less glossy and has a duskier throat and buff-washed underparts.<p>The eastern form D. n. cuttingi has a wing length of 99–106 mm (3.9–4.2 in), slightly larger than the nominate subspecies at 90–98 mm (3.5–3.9 in). Both subspecies can be distinguished from the similar Asian and common house martins by their black chin, black undertail coverts and much squarer tail.<p>This is an exceptionally fast-flying martin which gives an occasional short chi-i call in flight. It is otherwise a rather quiet bird, but it has a brief three-note breeding song.

Taxonomía

The Nepal house martin was first described by British entomologist Frederic Moore in 1854, and placed in a new genus Delichon created by Moore and American naturalist Thomas Horsfield. The specimen or its description was attributed by Moore to Brian Houghton Hodgson and early literature sometimes refers to it as Hodgson's martin. Some older taxonomic sources such as those by S D Ripley specify the binomial author as "Hodgson = Moore in Horsfield &amp; Moore, 1854". Its closest relatives are the two other members of the genus, the Asian house martin and the common house martin. This martin has a distinctive subspecies, D. n. cuttingi, described by American biologist Ernst W. Mayr in 1941 from a specimen taken near the Burma-Yunnan border. White-throated birds in the southern extension of the range are similar in appearance to the nominate subspecies, but because of their geographical separation are sometimes considered to be a third race, D. n. bartletti.Delichon is an anagram of the Ancient Greek term χελιδών (chelīdōn), meaning "swallow", and nipalense refers to Nepal, where the type specimen was obtained.

Nombre científico

Delichon nipalense

Autoridad

Moore, F, 1854

Orden

Passeriformes

Familia

Hirundínidos

Género

Delichon

Distribución y hábitat

The nominate subspecies D. n. nipalense breeds in the Himalayas from Garhwal east through Nepal, north-eastern India and Bangladesh as far as western Myanmar. The race D. n. cuttingi is found in northern Myanmar, along Myanmar's border with Chinese Yunnan and in northern Tonkin, Vietnam. The Nepal house martin is largely resident, but may move to lower altitudes when not breeding, and has been occasionally recorded in northern Thailand in winter. The range in Thailand is poorly known.<p>The habitat is river valleys and wooded ridges at 1,000–4,000 m (3,300–13,100 ft) altitude, although mainly below 3,000 m (9,800 ft). When not breeding, birds typically descend to 300 m (980 ft), and occasionally to 150 m (490 ft). The range of this species overlaps with that of the nominate subspecies of Asian house martin, although they breed at different altitudes. The height separation and the small differences in appearance seem sufficient to prevent interbreeding.

Migración

Especie residente

Comportamiento

Patrón migratorio: Especie residente.

Conservación

Tendencia poblacional: estable.

Tendencia poblacional

estable