Arthur William Baden Powell was born at Wellington on 4 April 1901, the son of Arthur Powell, a driver, and his wife, Minnie Sablofski. After attending primary schools in Parnell and Mount Eden, he went on to Auckland Grammar School in 1916. Following his training at Elam School of Art, he began a printing apprenticeship and during the 1920s worked as a free-lance commercial artist until 1929. An early passion for shell collecting combined with his fine illustrating skills soon saw him absorbed in his life’s work of conchology.
Baden, as he was known, published his first scientific paper on Mollusca at the age of 20. Within a decade, together with John Marwick in Wellington and Harold Finlay in Dunedin, he had become one of a strong trio publishing articles on Tertiary and living Mollusca. They were successors to Henry Suter, who had first given New Zealand conchology its high reputation overseas. On 19 December 1928, at Devonport, Baden Powell married Isabel Essie Gittos. They had one son.
An important era began for Powell in 1929 with his appointment to Auckland War Memorial Museum as conchologist and palaeontologist. Already expert with both living and fossil shells, he was to focus on some of the difficult families, including the minute rissoid snails, illustrating their shells with simple beauty and accuracy. He had already begun studying Tertiary fossils near Port Waikato and at Waiheke Island, and in the 1930s he conducted further studies at Wanganui, Cape Runaway and Castlepoint. He also began work on New Zealand’s large land snails. First he did a distribution study of the various species of the spectacular Paryphanta, and then another on the flax snails (Placostylus) of Northland and the Three Kings Islands.
In 1932 Powell was invited to join the British research ship Discovery II on its voyage around the Northland coast, which he later designated the Aupourian marine province. A new technique of dredge-sampling designed to retain the smallest shells revealed an astonishing 128 new species in 1937, and in 1940 he described another 66. He conducted studies at Stewart Island (1939), the Chathams (1940), and the Kermadecs (1958 and 1967). Although he never visited the far south, Powell wrote the reports on the Gastropoda of the Discovery II collections from Antarctica and the subantarctic region between 1931 and 1955, and the culminating paper in 1960. Other global projects were an important study of the living and fossil turrid gastropods (1942–69), and a monograph on patellid limpets (1973).
As well as producing more than 100 scientific papers, Powell wrote three notable books which, without sacrificing their scientific content, made enjoyable reading. The shellfish of New Zealand (1937) combined an indispensable checklist for specialists with a good commentary for amateurs and full illustrations. The museum handbook, Native animals of New Zealand (1947), became a household work and was in high demand when local natural history books were still scarce. It was familiar in homes and schools with its yellow soft cover and clear black-and-white figures of 411 land, marine and freshwater animals; 140,000 copies were sold. The New Zealand Mollusca (1979), a 500-page publication, was the culmination of 50 years’ singlehanded work designed to replace Suter’s long-outdated 1913 manual. Compared with Suter’s 1,079 species, Powell estimated that there were 2,256, and he produced clear illustrations with concise, accurate descriptions.
Powell excelled as a communicator, particularly in his newspaper articles and his generous response to enquiries. An inspiration to young naturalists, he recalled his own debt to T. F. Cheeseman, whose mentor had been Charles Darwin, and he felt the same mission to encourage others. Several who attended his Auckland Museum Conchology Club (founded in 1931) were to rise to leading scientific and academic posts.
Baden Powell was assistant director of the Auckland War Memorial Museum from 1936 until his retirement in 1963. His early training enabled him to set new standards of museum design and layout and his exhibitions were masterly in conception and presentation. Resourceful and practical, he did his own dioramas, watercolours, photography and vintage hand-printed labels, often made storage trays and glass-topped boxes in his lunch hour, and edited and printed museum publications.
His scientific investigation carried over into weekends and holidays while he was on the family launch. In 1937 he completed a study of the animal communities at the bottom of the Auckland and Manukau harbours, including snapper in their feeding grounds. A classic of its kind, this study provided a baseline from which to record changes over the next 50 years.
Powell became a fellow of the Royal Society of New Zealand in 1940 and was awarded the Hector Memorial Medal and Prize in 1947. He represented the Auckland Institute and Museum on the Society’s Council from 1958 to 1961 and was elected a fellow of the Art Galleries and Museums Association of New Zealand. In 1956 the University of New Zealand conferred on him an honorary DSc. He was made a CBE in 1981. His wife, Isabel, died in 1976, and on 2 December 1978 he was married at Whangarei to Ida Madoline Worthy (née Hayes), an old family friend and enthusiastic shell collector. Baden Powell died at Auckland on 1 July 1987 survived by his second wife and his son from his first marriage.
Powell embodied the New Zealand tradition of the self-taught naturalist who, with driving energy and practical skills, had risen to master a wide field. A colleague, R. K. Dell, remembered him as ‘a shy man, rather diffident and formal with strangers, but expanding in company he knew’. His finest memorial was the enhanced appreciation of nature he inspired in those who read his semi-popular books.