Red-naped Ibis

The red-naped ibis (Pseudibis papillosa) is a large, dark ibis native to the Indian subcontinent. Adults are about 60–68 cm long, have a wingspan of roughly 90–115 cm and weigh around 1.1 kg. The body is dark brown to black, the wings show a strong metallic green and purple sheen, and a conspicuous white patch is visible on the shoulder. The long downcurved bill and reddish legs give the bird a typical ibis silhouette.

The most distinctive feature is the bare black head topped by a bright crimson patch of warty skin across the crown and nape. Unlike many other ibises, the species is often found well away from large open water bodies and may be encountered walking through wet grassland, fallow fields and other open country.

Red-naped ibises use wetlands, river margins, shallow pools, wet grassland, grazing areas and farmland. A study in Rajasthan found far more ibises throughout the year in landscapes rich in wetlands than in areas dominated by agriculture, showing how important wetlands are even for this flexible species.

Within agricultural landscapes, fallow fields can still be important. In the same study most birds seen away from wetlands were in fallow fields, while none were recorded in standing crops. The combination of wetlands and open feeding ground therefore appears much more valuable than intensive cropland alone.

The red-naped ibis feeds on insects and other invertebrates, frogs, small reptiles, fish and other small animals, and also takes some seeds and plant material.

The long bill is more than a simple pair of forceps. Like other probing ibises, the red-naped ibis has a dense sensory system near the bill tip that can detect tiny vibrations produced by hidden prey in mud or soil. This remote-touch system allows a bird to locate an animal without seeing it directly and helps explain why probing remains effective in opaque water and soft ground.

Birds walk slowly across wet ground, shallow water or open soil and probe repeatedly with the long bill, often sweeping it from side to side while searching beneath the surface. Studies in western India have documented several additional techniques, including probing at different depths, pecking from the surface and dragging or flipping material with the bill.

The species can also exploit unusual feeding sites such as wastewater areas and refuse. There is even a published record of a red-naped ibis feeding on flower nectar, illustrating how broad its opportunistic feeding behaviour can become.

Red-naped ibises are mainly active by day. They often forage alone, in pairs or in small groups, but may gather more densely where food is concentrated. At night they can roost communally in trees or on small islands, so a bird that appears solitary while feeding may still join other ibises at a shared resting site after dusk.

Between bouts of foraging, the birds rest and preen in open areas and move readily between wetlands and nearby dry ground during the day. This combination of solitary or loose daytime activity and communal roosting gives the species a more flexible social pattern than its often isolated appearance suggests.

Red-naped ibises usually nest as isolated pairs rather than in large colonies. The nest is a large stick platform high in a tree, often in an open landscape where the adults can fly directly to nearby feeding areas. Clutches are generally small, usually two to four eggs, and both adults take part in nesting duties and care of the young.

A small breeding study published in 2019 followed six nests in agricultural landscapes in Punjab. Breeding activity was recorded from March to November, with most nests found between March and July. In nests where incubation could be followed, it lasted about 30–32 days. Both parents shared incubation and feeding, and the young became capable of flight after around 45–50 days.

A survey of agricultural landscapes in Nepal from 2018 to 2022 recorded 14 nests across eight districts in 2022. More than half were outside protected areas, and large trees were clearly important: silk-cotton trees (Bombax ceiba) held half of the recorded nests and sal (Shorea robusta) almost a third. The average nest tree was over 20 m tall.

The species can also adapt when such trees are scarce. Surveys along a highway in Haryana in 2023 found nests on 26 electricity pylons and one mobile-phone tower, generally 15–20 m above the ground. This shows considerable flexibility, while large trees remain important natural nesting sites.

The red-naped ibis is classified as least concern on the IUCN Red List. It is endemic to the Indian subcontinent and remains widespread, although abundance varies considerably between landscapes and the species is much less numerous in some neighbouring countries than in India.

In India the population has increased strongly over the long term, while the trend in recent years has been approximately stable. The species is therefore doing well across much of the country, but wetlands and large nesting trees remain important parts of its habitat.