Hodgson studied all aspects of natural history around him including material from Nepal, Sikkim and Bengal. He amassed a large collection of birds and mammal skins which he later donated to the
British Museum. As a result of an order by the Nepalese court he was unable to travel outside Kathmandu while living there and he therefore employed local hunters to collect his specimens for him. One of them was
Raj Man Singh, but many of the paintings are unsigned. Most of them were subsequently transferred to the Zoological Society of London and the Natural History Museum. His studies were recognised and the Royal Asiatic Society made him a member in 1828 and the
Linnean Society of London elected him as a fellow in 1835. The Zoological Society of London sent him their diploma as a corresponding member. The
Société Asiatique de Paris and the Museum d'Histoire Naturelle also honoured him. Around 1837 he planned an illustrated work on the birds and mammals of Nepal. The Museum d'Histoire Naturelle de Paris and other learned bodies came forward as supporters, three hundred and thirty subscribers registered in India, and in July 1837 he was able to write to his father that the means of publication were secured: "I make sure of three hundred and fifty to four hundred subscribers, and if we say 10 per copy of the work, this list should cover all expenses. Granted my first drawings were stiff and bad, but the new series may challenge comparison with any in existence." He hoped to finish the work in 1840. In 1845, he presented 259 bird skins to the Natural History Society of Northumberland, Durham, and Newcastle upon Tyne. After retiring to Darjeeling he took a renewed interest in natural history. During the spring of 1848 he was visited by Sir
Joseph Hooker. He wrote to his sister Fanny: He wrote in 1849 on the physical geography of the Himalayan region, looking at the patterns of river-flows, the distributions and affinities of various species of mammals, birds and plants while also looking at the origins of the people inhabiting different regions.
Allan Octavian Hume said of him: Many birds of the Himalayan region were
first formally described and given a
binomial name by Hodgson. The list of world birds maintained by
Frank Gill,
Pamela Rasmussen and
David Donsker on behalf of the
International Ornithological Committee credits Hodgson as the
authority for 29
genera and 77
species.
Charles Darwin in his
Variation of Animals and Plants under Domestication, when discussing the origin of the domestic dog, mentions that Hodgson succeeded in taming the young of the race
primaevus of the
dhole or Indian wild dog (
Cuon alpinus), and in making them as fond of him and as intelligent as ordinary dogs. Darwin also cited a 1847 article by Hodgson on the varieties of sheep and goats in the Himalayas. ==Personal life and death==