Red-naped Ibis

Identificazione

The red-naped ibis is a large black bird with long legs and a long downcurved bill. The wing feathers and tail are black with blue-green gloss while the neck and body are brown and without gloss. A white patch on the shoulders stands out and the top of the featherless head is a patch of bright red warty skin. The warty patch, technically a caruncle, is a triangular patch with the apex at the crown and the base of the triangle behind the nape that develops in adult birds. The iris is orange red. Both sexes are identical and young birds are browner and initially lack the bare head and crown. The bills and legs are grey but turn reddish during the breeding season. The toes have a fringing membrane and are slightly webbed at the base.<p>They are usually silent but call at dawn and dusk and more often when nesting. The calls are a series of loud braying, squealing screams that descend in loudness. Nocturnal calling is rare and has been observed in urban settings.<p>This species can be confused with the glossy ibis when seen at a distance but the glossy ibis is smaller, more gregarious, associated with wetlands and lacks the white on the wing and has a fully feathered head.

Tassonomia

The species was first given its scientific name by Temminck in 1824. He placed it in the genus Ibis but it was separated into the genus Inocotis created by Reichenbach and this was followed by several major works including the Fauna of British India although the genus Pseudibis in which Hodgson had placed the species had precedence based on the principle of priority. The species included the white-shouldered ibis as a subspecies P. papillosa davisoni from 1970s but that is now treated as a full, although closely related species. The main morphological difference between the two species is seen in the crown and the upper neck. While P. papillosa has a patch of red tubercles on the back of the crown, P. davisoni lacks it. Also, adult P. papillosa have a narrow, bright red mid-crown that becomes broader on the hindcrown, whereas, adult P. davisoni has a bare pale blue middle hindcrown that extends to the upper hindneck and forms a complete collar around the upper neck. Using nuclear and mitochondrial DNA, the species has been placed within the subfamily Threskiornithinae in a clade that includes both New and Old World members.

Nome scientifico

Pseudibis papillosa

Autorità

(Temminck, 1824)

Ordine

Pelecaniformi

Famiglia

Threskiornithidae

Genere

Pseudibis

Areale e habitat

The red-naped ibis is widely distributed in the plains of the Indian Subcontinent. In Rajasthan, it is common along the Aravalli mountains but entirely avoids using the trees on the mountains. The red-naped ibis uses lakes, marshes, riverbeds, irrigated farmlands, dry fallow fields, villages, towns and cities. More wetlands on the landscape attract a greater number of red-naped ibises, but birds forage largely in dry fields increasing use of wetlands for foraging during summer. In semi-arid areas, it is commonly seen in small flocks of 2-4, which could be family groups, with larger groups being relatively rare. Fewer ibises were counted in wetter locations and seasons. <p>It is a common breeding resident in Haryana, Punjab, Rajasthan and the Gangetic plains. It extends into southern India but is not found in the forested regions or the arid zone of the extreme southeast of the peninsula or Sri Lanka. In lowland Nepal, most foraging red-naped ibis were seen in agricultural fields, but most nests were seen in forests. Red-naped ibis commonly use villages, towns and mega-cities seeking food, nesting and roosting. <p>The red-naped ibis is largely diurnal in its foraging and other activities, at night roosting communally on trees or on islands. Nocturnal activities such as loud calling is rare.

Migrazione

Specie stanziale

Comportamento

Comportamento migratorio: Specie stanziale.

Conservazione

Tendenza della popolazione: in diminuzione.

Tendenza della popolazione

in diminuzione