In 1891, he established a museum for his collections on his property at Coomooboolaroo 14 mi (23 km) south of Duaringa, Queensland, Australia.
Naturalist Albert Stewart Meek who was a friend of Barnard and spent some time at Coomooboolaroo in the 1890s made Lord Rothschild aware of this collection.
Barnard wrote many ornithological articles for the Descriptive catalogue of the nests & eggs of birds found breeding in Australia and Tasmania.
(1889), Alfred John North's oology studies published as the Australian Museum's catalogue number twelve.
The couple had seven children, including ornithologist Charles Ashmall Barnard (1867-1942), founding member and later president of the Royal Australasian Ornithologists Union, and Henry "Harry" Greensill Barnard (1869-1966), a zoologist after whom Lasiorhinus krefftii barnardi, a subspecies of the Northern hairy-nosed wombat (Lasiorhinus krefftii) was named.