[1] While in Darjeeling, he took a keen interest in the local zoology, sending specimens to England for identification.
Belomys pearsonii was named after him by his friend from medical student days, J. E. Gray, in 1842.
[citation needed] Pearson was made curator of the Asiatic Society in July 1833 and held the position until 1835 as a favour to James Prinsep.
During this period he described the hispid hare and a new species of kingfisher, Pelargopsis amauroptera.
[3] This was a period of flux at the Asiatic Society of Bengal and there were complaints from a Dr William Jameson that Pearson had not maintained the museum in order.