Kunwar "Billy" Arjan Singh (15 August 1917 – 1 January 2010) was an Indian hunter turned conservationist and author. He was the first who tried to reintroduce tigers and leopards from captivity into the wild. Billy Arjan Singh died at his original farmhouse Jasbir Nagar on 1 January 2010. Early life Kunwar "Billy" Arjan Singh was born in Gorakhpur on 15 August 1917 as the second son of Kunwar Jasbir Singh, CIE (1887–1942), a member of the royal Ahluwalia dynasty of Kapurthala. His grandfather was Raja Harnam Singh and his uncle was Raja Maharaj Singh. Rajkumari Amrit Kaur was his aunt and his elder brother was Air Vice-Marshal Kunwar Jaswant Singh, PVSM (1915–1963). In 1940, Singh was commissioned as a Second Lieutenant in the British Indian Army and was posted to the south of Iraq. Hunter turned conservationist Singh described how in his youth he had been an insatiable hunter. However, one day having shot a young leopard in the lights of his vehicle, he dramatically changed his view of hunting, feeling nothing but revulsion for killing and vowing that from then on he would pursue the cause of conservation. His first major project was to save a herd of barasingha in the neighbouring Sathiana range of the forestry reserve at Dudhwa. In 1976, he was awarded the World Wildlife Fund's gold medal, the WWF's premier award, for his conservation work. He was also largely responsible for persuading the then Prime Minister, Indira Gandhi, to transform Dudhwa into a national park. Re-introduction of big cats Singh's conservation efforts for wildlife are best known for his reintroduction of leopards and a tiger into the wild of Dudhwa National Park. He started by bringing up an orphaned male leopard cub named Prince, which he successfully reintroduced to the wild in 1973. To provide Prince with a mate he subsequently raised two orphaned female leopards cubs, Harriet and Juliette. In July 1976, he acquired a hand-reared female tiger cub named Tara from Twycross Zoo in the United Kingdom, and reintroduced her to the wild in the Dudhwa National Park with the permission of India's then Prime Minister Indira Gandhi. In the 1990s, some tigers were observed in the protected area, which had a Siberian tiger phenotype of a large head, pale pelage, white complexion, and wide stripes, and were therefore suspected to be Bengal-Siberian tiger hybrids. Billy Arjan Singh sent hair samples of