In 1846 The Rana Prime Minister Jung Bahadur protected the wildlife of Chitwan Valley by maintaining a hunting reserve in the area exclusively for the use of the ruling classes and their guests. Hunting was normally conducted during winter. Certain methods were used for hunting such as the ring method, in which a big circle of elephants would entrap the hunted animal. The number of elephants required for this process was quite large.
Stationary hunting from a perch of Machan , trapping in pits, Kheddah method, etc., were other methods of hunting.
The fall of the Rana dynasty opened up Chitwan's forests for new settlers from the hills in 1951.
After declaration of the Terai as a malaria-free zone, people from the hills migrated to the Terai. In less than a decade, the population of the Chitwan increased from 36,000 in 1950 to 100,000 in 1960. This caused loss of habitat for wildlife species which ultimately became a threat to their survival.
In 1959 naturalist EP Gee recommended the establishment of a national park to the north of the Rapti river and proposed a rhinoceros sanctuary to the south of the river. HMG/Nepal set aside 800 sq. km for a rhinoceros sanctuary. In 1968 GJ Caughley and HR Mishra estimated 81 to 108 rhinos in the area.
King Mahendra approved the establishment of Royal Chitwan National Park as the first national park of Nepal in 1970.
Park was declared a World Heritage Site by UNESCO in 1984.
446 to 466 rhinoceros were estimated in Chitwan National Park in 1994.
Nepal was home to over 544 rhinos in 2000, with Chitwan National Park having the second-largest population in the world.
The count named as "Rhino Count 2005? found the rhino population had decreased by 160 in the last five years, 2000 to 2005. Of the total, 94 were killed for horns. 84 out of 87 rhinos translocated to Bardiya were killed by poachers.
Now the fauna of the world, one-horned rhino, has been struggling for its existence.