Birds of the Indian Subcontinent

Biogeographic Zones of the Indian Subcontinent

The Indian Subcontinent rests largely on the Indian Plate and encompasses India, Pakistan, Nepal, Bhutan, Bangladesh and Sri Lanka, along with Andaman and Nicobar Islands in the Bay of Bengal, and the Maldives and Lakshadweep archipelagos in the Arabian Sea. Birds of South Asia: the Ripley Guide also includes Afghanistan (usually clumped with Central Asia) and the Chagos Peninsula (the group of islands in the Indian Ocean south of the Maldives). In recent times, the Indian Subcontinent is often referred to as South Asia.

The Indian Subcontinent is separated from Central Asia by the Himalayas. The mountain barriers to the northwest and northeast are the Hindu Kush (in Afghanistan and Pakistan) and Arakan (bordering northeast India and Myanmar) respectively. The seas/oceans that fringe its southern expanse are the Arabian Sea to the west, the Bay of Bengal to the east, and the Indian Ocean to the south.

Profile of the Avifauna of the Indian Subcontinent

The Indian Subcontinent has one of the most diverse avifauna on earth, brought about by the diversity of climatic and physical features of the landmass, which have given rise to an assortment of habitat types ranging from desert to montane forests. With bird studies, birdwatching and bird photography picking up momentum especially in recent years, new species are getting discovered and described to science, the most spectacular being the Bugun Liocichla in 2006 from the Eaglenest Sanctuary in Arunachal Pradesh.

The Siberian Crane, which was a regular winter visitor to the Keoladeo National Park in Rajasthan, has not been recorded in India since the winter of 2001– 2002. Two species that were considered extinct, Jerdon’s Courser and Forest Owlet were rediscovered, but the status of the former is uncertain again.

The IUCN (International Union for Conservation of Nature) has placed 17 species that occur in the Subcontinent as Critically Endangered (some of which are probably extinct): Himalayan Quail, Baer’s Pochard, Pink-headed Duck, Siberian Crane, Great Indian Bustard, Bengal Florican, White-bellied Heron, Christmas Island Frigatebird, Sociable Lapwing, Spoon-billed Sandpiper, Jerdon’s Courser, Red-headed Vulture, White-rumped Vulture (or Oriental White-backed Vulture), Indian Vulture (or Long-billed Vulture), Slender-billed Vulture and Yellow-breasted Bunting and Bugun Liocichla. Other than these, there are species categorized as Endangered (26 species), Vulnerable (77 species), and Near-Threatened (92 species), bringing the total number of threatened birds to 212 species.

Based on the residency status and migration/ movement pattern, the birds of the Indian Subcontinent may be grouped as follows:

Residents

The avifauna of the Indian region comprises typical birds of the Indomalayan realm (e.g., leafbirds, fairy-bluebirds, barbets and junglefowl), and characteristic groups of the Indian Subcontinent (e.g., pheasants, pittas, Old World babblers and flowerpeckers). There is also a good number of Palearctic birds in the Himalayas (e.g., Eurasian Jackdaw,, snowcocks, snowfinches, nuthatches, treecreepers, and accentors). And, Afrotropical groups of North Africa and West Asia (e.g., coursers, bustards, honeyguides and hypocolius), along with families that are common to both the Afrotropical and Indomalayan realm (e.g., bulbuls, sunbirds and weavers).

Some of the world’s most cosmopolitan species (e.g., Peregrine Falcon, Osprey, Barn-Owl, and Rock Dove/Rock Pigeon) have resident populations in the Indian Subcontinent. Populations of some of the resident species get augmented in winter by an influx of migrant populations of their kin from the Palearctic region, e.g., Great White Egret, Grey Heron, Glossy Ibis, Eurasian Spoonbill, Common Kestrel, Peregrine Falcon, Eurasian Coot, Kentish Plover, Little Ringed Plover, Gull-billed Tern, Common Hoopoe and House Sparrow.

Demoiselle Crane are common winter visitor to parts of the Indian Subcontinent

Winter Migrants

About 23% of the species reported in the Indian Subcontinent are winter migrants. These originate largely from the Palearctic region beyond the Himalayas, breeding mainly in northern Asia and the countries of Central Asia. A few species come from as far as extreme Western Europe. More well-known and common among the winter migrants are the raptors, storks, ducks and geese, waders (shorebirds), cranes and the passerines comprising swallows, flycatchers, warblers, thrushes, chats, wheatears, redstarts, pipits, wagtails, buntings and finches.

Some of the migratory waterbird species have populations/races that breed (mostly in small numbers) in the Trans-Himalayas in summer, e.g., Bar-headed Goose, Ruddy Shelduck, Mallard, Lesser Sand Plover, Common Sandpiper, Common Redshank and Brown-headed Gull.

Summer (Breeding) Migrants

Similar to the migration pattern of the extralimital migrants to the Subcontinent is the movement of birds to the Himalayas and the Northeast hills in summer to breed. Post-breeding, these species winter in northern India or migrate further south into the Peninsula. These summer (breeding) migrants behave like true migrants from the Palaearctic, and this is like a compacted case of the North-to-South migration brought about by the presence of the Himalayas and the adjoining hills, which due to their elevation, mimic the conditions of the breeding grounds in the northern climes.

Altitudinal Migrants

A much shorter migration is undertaken by resident Himalayan birds. These species move down to the lower reaches and foothills of the range with the advent of winter (to escape the cold conditions) and return with the onset of spring. Examples are Grandala, Ibisbill, Wallcreeper and treecreepers. Other than arboreal species, the cursorial pheasants and their allies undertake such migrations, travelling largely on foot. Attitudinal migration by resident birds also takes place in the Western Ghats, for example, in the Square-tailed Bulbul, with birds moving to the foothills during the cold weather.

Local (Seasonal) Migrants

Many resident species of the Indian Subcontinent undertake regular, seasonal internal movements, while some undertake irregular, nomadic movements. Well-known among the local (seasonal) migrants are the Indian Pitta, Indian Paradise-Flycatcher, Indian Golden Oriole, and Blue-tailed Bee-eater.

Flamingos in the Mahul-Sweri Creek

Among the resident bustards, the Lesser Florican is a species that is presumed to undertake seasonal, long-distance movements. BNHS studies have documented that it breeds regularly in the protected grassland enclosures of Rollapadu Wildlife Sanctuary, Andhra Pradesh. It is conjectured that the birds migrate and breed in winter in the southern parts of the Peninsula if the monsoon has been poor in their northern strongholds.

Among the waterbirds occurring in the Indian Subcontinent that undertake significant seasonal/ nomadic movements are the flamingos. Both the Greater Flamingo and Lesser Flamingo largely breed in the Kutch region of Gujarat, and from winter up to the onset of the southwest monsoon, flamingos are recorded from many sites in the mainland, especially in peninsular India. However, the origin/origins of these wintering birds are still uncertain. Till date, the movement pattern of these birds into southern India (and elsewhere) is unknown with no recoveries either from the nearly two hundred young individuals ringed in the 1940s from the Great Rann of Kutch, or from birds ringed over the decades from BNHS field stations in southern India. Likewise, there is uncertainty on the origins of the Lesser Flamingo wintering in the Subcontinent. Since the mid-1990s Lesser Flamingos have been recorded in the Mahul-Sewri Creek of Mumbai. This when compared with the low numbers and scarce nesting records reported in Kutch in the past, and also the significant numbers reported in winter in Kutch (as in the wetlands around Mumbai) in recent years, suggests movements of birds between Africa (the stronghold of the species) and India.