Dudhwa is tiger country - a living testament to Arjan Singh’s determination to protect the big cats of the Terai region. Though outnumbered by the Bengal tigers, the wildlife reserve does have a sizeable population of leopards, as is evident from cases of man-animal conflicts in agricultural fields around the park’s fringes. Home to half the world’s population of swamp deer or barasinghas, Dudhwa is one of the few parks in India inhabited by five types of deer - sambar deer, barking deer, spotted deer, hog deer and barasinghas. It is also possible to sight sloth bears, jungle cats, fishing cats, and hispid hares here. Pachyderms such as one-horned rhinoceroses and wild elephants feed off the tall grasses that reach new heights soon after the monsoons. While rhinoceroses were successfully reintroduced in Dudhwa from Assam and Nepal in 1984, the vulnerable hispid hares were rediscovered here in the same year. Tourists occasionally get to see mugger crocodiles lurking around the sandy banks of the Suheli and the Mohana rivers as well. With some luck, one may also chance upon swimming otters or monitor lizards searching for crocodile eggs near one of the many lakes, rivers, rivulets or streams here. The endangered gharials are rarely spotted in the Girwa river of Katarniaghat Wildlife Sanctuary. Dudhwa gets abundant rainfall, and seasonal floods are common here. Dudhwa’s thick grasslands fed by the fertile Gangetic plains and numerous water bodies attract a large number of migratory birds during the winters, making it a birdwatchers’ paradise. Besides different types of storks, eagles, cranes and owls, this wildlife reserve also boasts of the critically-endangered Bengal floricans. Birdwatchers throng Dudhwa every year to watch the mesmerising mating ritual of these floricans that were once found throughout the Terai region. The Indian pittas, Asian paradise flycatchers and emerald doves add strokes of colour to the otherwise green canvas in the park. A major destination for avid birders in the country, the Dudhwa Tiger Reserve has around 450 of India’s 1300-odd avian species making an appearance every year. Egrets, cormorants, herons, hornbills, bulbuls, drongos, kingfishers, mallards, warblers and woodpeckers are also found here.

The Manduk Mandir/Frog Temple constructed by the Oyal kings makes for an interesting stopover if you are travelling from Hargaon to Lakhimpur-Kheri and Dudhwa. With a base built in the shape of a frog, the 200-year-old temple is dedicated to Lord Shiva. Diwali is one of this temple’s bigger festivals.

Livestock grazing and human encroachment pose a serious threat to Dudhwa’s biodiversity. The areas surrounding the fringes of the reserve, where sugarcane cultivation is common, witness frequent conflicts between the big cats and human beings. Wild animals that venture into these fields are often killed in retaliation. With Nepal on the other side of the Tiger Reserve’s border, poaching and related smuggling are also serious problems. Logging and forest fires have taken a toll on the park as well.