Arthur William Baden Powell CBE (4 April 1901 – 1 July 1987) was a New Zealand malacologist, naturalist and palaeontologist, a major influence in the study and classification of New Zealand molluscs through much of the 20th century. He was known to his friends and family by his third name, "Baden".
The name Baden had been a given name in a Powell family since 1731, when Susannah Powell née Thistlethwayte (1696-1762) gave to her child (1731-1792) the maiden name of her mother, Susannah Baden (1663-1692). The name Baden, particularly when associated with the surname Powell, became famous in 1900-1901, the year Arthur William Baden Powell was born, because of the Siege of Mafeking, the most famous British action in the Second Boer War, which turned the British Commander of the besieged, Robert Baden-Powell, into a national hero. Throughout the British Empire, babies were named after him. No family connection has yet been established between Arthur William Baden Powell and Robert Baden-Powell.
Powell was born at Wellington, New Zealand, on 4 April 1901. His schooling was in Auckland, and he trained in printing at the Elam School of Fine Arts. This training, and his interest in conchology, set him on his life's work. He started writing scientific papers on mollusca in 1921, and became one of the few experts in New Zealand shellfish.
Powell married Isabel Essie Gittos on 19 December 1928, at Devonport in Auckland. They had a son.
He was appointed to the Auckland War Memorial Museum as palaeontologist and conchologist in 1929, working on some lesser-known mollusc families. He also studied New Zealand’s big land snails, the Paryphanta, and the Placostylus flax snails. From 1932 Powell participated in dredging expeditions on the British research ship Discovery II exploring coastal Northland and discovering large numbers of new species. Other field trips from the 1930s to 1960 took him to Stewart Island, the Chatham Islands, the Kermadec Islands and the Antarctica and Subantarctic region, resulting in many important papers.