Birding the Terai: Chitwan, Koshi and Beyond

Nepal has recorded close to 900 bird species, a remarkable number for a country of its size, and a large share of them live in or pass through the lowlands. The reason is variety. In a strip of land rarely more than 50 km wide, the Terai packs together sal forest, riverine forest, tall grassland, oxbow lakes, braided rivers and farmland, all at the meeting point of Himalayan and Indian bird communities.

In winter, birds from Central Asia, Siberia and the Tibetan plateau fly south over the Himalaya and settle on the Terai's lakes and rivers. In spring and summer, breeding visitors arrive from the south, and resident birds are in full song. The result is that a keen birder can see 200 or more species in a week, and the very best sites hold birds found almost nowhere else in the world.

Chitwan is the obvious place to start. Its bird list passes 500 species, and its mix of habitats means you can move from grassland to forest to river in a single morning. In the grasslands look for Bengal florican, a large, critically endangered bustard whose males leap into the air in spring display, and for grassland babblers and warblers that are specialities of this habitat. The sal forest holds woodpeckers, minivets, drongos and hornbills, including oriental pied and the huge great hornbill.

Rivers bring kingfishers, including the stork-billed kingfisher, plus herons, storks, lesser adjutant and, in winter, ducks and ruddy shelduck on the sandbanks. A dawn canoe on the Rapti is one of the best birding experiences in Nepal. Just south of Bharatpur, Bishazari Tal, whose name means twenty thousand lakes, is a group of oxbow lakes and marshes in the buffer zone, listed under the Ramsar Convention in 2003. It is excellent for waterbirds, jacanas, storks and raptors.

Sauraha is home to the Bird Education Society, a local conservation group that runs bird walks and education programmes. Its members share recent sightings and can recommend local bird guides.

Koshi Tappu Wildlife Reserve, in the far east of the Terai, was created in 1976 to protect Nepal's last wild water buffalo and became the country's first Ramsar site in 1987. The reserve lies on the floodplain of the Sapta Koshi, a vast braided river of channels, islands, reed beds and grassland. Downstream, the Koshi Barrage on the Indian border creates open water that draws huge numbers of ducks, gulls, terns and waders in winter.

Koshi is the place for waterfowl. In winter, rafts of ducks gather on the barrage, and rare species such as the critically endangered Baer's pochard have been recorded in some years. The reeds and grassland hold swamp francolin, a noisy but shy gamebird, and grassland specialists. Black-necked stork, lesser adjutant and many raptors are seen. Boat trips on the river add the chance of the Gangetic river dolphin.

Further west, Lumbini is famous for one bird above all: the sarus crane, the world's tallest flying bird, which nests in the rice fields and wetlands of Rupandehi and Kapilvastu. Pairs stand head-high in the paddies, and their duets carry across the fields. Small reserves and the grounds around Lumbini's sacred garden are good places to look, and the cranes fit naturally into a pilgrimage visit.

Bardia National Park, on the Karnali, combines forest birds with river species and grassland specialities. In the far west, Shuklaphanta National Park protects one of the largest grasslands in the Terai, and with it important populations of Bengal florican and other grassland birds. Nearby, Ghodaghodi Tal in Kailali is a Ramsar-listed lake system with good waterbirds and few visitors.

This table summarises the main Terai birding sites. Many birders combine two or three of them in a week or ten days, linking them by road along the East-West Highway or by short domestic flights.

A week is enough to see the two great sites properly. Spend the first night in Kathmandu, with an optional morning on the forested slopes of Phulchowki for hill birds before you head south. Fly to Bharatpur and give Chitwan three nights: one full day in the grassland and forest with a jeep, one dawn canoe on the Rapti followed by a morning at Bishazari Tal, and short walks in the community forests around Sauraha at the start and end of each day.

Then fly east via Kathmandu to Biratnagar and drive to Koshi Tappu for three nights. Be at the Koshi Barrage at sunrise on the first full day, take a boat on the river and walk the embankments in the evenings. On the last day, work the fish ponds, paddy fields and reed edges around Kusaha for anything still missing from your list, then fly back to Kathmandu.

With ten days, add Lumbini for sarus cranes on the way west, or Shuklaphanta in the far west for grassland specialities in spring. Keep at least one spare half-day in every plan; fog, rain or a good tip from a local guide often changes the best use of a morning.

November to March is the main season, when winter visitors are present, the weather is dry and mornings are cool. Waterfowl numbers at Koshi and on Chitwan's lakes peak from December to February. March to May adds breeding residents and summer visitors such as pittas and cuckoos, and many birds are easier to find because they are singing; the downside is rising heat, which pushes birding into the early morning and evening.

From June to September the monsoon makes access difficult. Tracks close, rivers flood and the heat and humidity are heavy, though some breeding birds are at their best. For a first trip, February and early March offer the best balance: late winter visitors, early breeders, shorter grass and comfortable temperatures.

Hire a specialist bird guide. Chitwan and Koshi both have local guides with excellent ears and years of field experience, and they know where scarce species have been seen recently. Inside national parks, a licensed guide is required for all activities. Bring good binoculars; a spotting scope is very useful at Koshi and on the lakes.

Start early. The first two hours after dawn are the most productive, and in winter fog can hang until mid-morning, so plan grassland visits for when it lifts. Dress in neutral colours, carry water and snacks, and respect closed areas, especially during the breeding season. Share your sightings with local groups such as the Bird Education Society; records help conservation.

• Binoculars: 8x42 or 10x42 are ideal
• Scope: very useful at Koshi Barrage and on lakes
• Field guide: a South Asian or Nepal bird guide, or a good app
• Clothing: neutral colours, layers for cold winter mornings
• Permits: park and reserve fees are charged per day; check current status before you travel