From Lonely Planet: "From the 19th century on, the Chitwan Valley was a centre for the hunting trips that British and Nepali aristocrats found so entertaining. ... Yet occasional hunting forays into the park did not seriously jeopardize the Terai's wildlife. In fact, the region's status as a hunting reserve probably helped protect it. However, after the success of the malaria eradication program that began in 1954, the survival of tigers and rhinos was soon threatened."
"The national park was proclaimed in 1973 and since that time the animal population has rebounded. Chitwan now contains an estimated 465-plus rhinos and 80 tigers, quite apart from 50 other species of mammals and over 450 different types of bird. ... Today the park offers one of the finest wildlife experiences in Asia..."