Rosa Olga Jensen was born at Halfmoon Bay, Stewart Island, on 3 June 1900, the third child of Mary Elizabeth Leask and her husband, Newton Julius (Hans) Jensen, a fisherman and later a farmer. Educated at Halfmoon Bay School and Southland Girls’ High School, Invercargill, Olga, as she was known, then became a probationary teacher at Waikiwi School. She taught at Longridge Village and Menzies Ferry schools until her marriage to Arthur Borne Vickery, also a schoolteacher, on 13 May 1921 at Invercargill. They were to have one daughter.
Arthur’s sudden death on 5 March 1923 forced Olga to resume teaching. On 9 April 1924 at Stewart Island she married Norman Francis Sansom, a carpenter and later a Presbyterian minister. They lived initially at Invercargill, then at North Taieri, before returning to the Invercargill area in 1937. They had a daughter and a son.
Olga began helping at the Southland Museum, and in June 1948 was appointed an honorary curator. Four years later, in March 1953, she became director, a position she retained until 1959. Aided only by volunteers, she began to expand the museum’s scope: she developed natural history displays, set up a pioneer cottage in the museum, taught visiting school classes, and identified insect, plant and seashore specimens for the public. For over 50 years she collected botanical specimens for scientific study, including seaweeds, alpine and bog plants, ferns and lichens. Her expertise was acknowledged by her peers in 1956 when she was asked to deliver the Banks Lecture on botany at the Royal New Zealand Institute of Horticulture’s annual conference.
Olga Sansom shared her knowledge with senior biology classes at Southland Girls’ High School, accompanying them on field trips tramping in Fiordland and to local estuaries, wetlands and saltmarsh areas. On excursions she insisted that specimens be taken only when necessary and that the environment be left untainted. Her staunch support for conservation was tempered, however, by realism: ‘Conservation should not be done just for conservation’s sake,’ she argued; ‘the human factor should be considered’.
An active broadcaster, she gave correspondence school lectures and general talks about natural science on the radio. For three years from 1962 she filed a monthly Stewart Island newsletter for the national programme. She wrote two social histories of Stewart Island and was a regular book reviewer (especially of scientific works) and feature writer for the Southland Times. She also contributed articles to New Zealand’s Heritage and New Zealand’s Nature Heritage on topics as varied as the oyster and the muttonbird.
A keen and knowledgeable birdwatcher, particularly of Australian species self-introduced to New Zealand, Olga Sansom was a foundation member of the Ornithological Society of New Zealand and a member of its national council for three years. She was honorary secretary of the Southland branch of the Royal Society of New Zealand from 1952 to 1959. While natural science was her main interest, she was also a foundation member and councillor of the Southland Art Society and the local university association. She usually travelled by bicycle around Invercargill and was known for her love of sea bathing and gardening.
During the Second World War Norman Sansom had served abroad as a chaplain. After the war he taught at Southland Boys’ High School and conducted church services at vacant parishes most weekends. In 1962 he was appointed minister at Oban Presbyterian Church and the Sansoms, now in semi-retirement, returned to Stewart Island. Olga, an energetic woman, who considered ‘A certain amount of tension is good for anybody’ because it ‘spurs you on to do things’, continued to write.
About 1971 they moved to Gore to be close to other family members. Here, on 23 August 1985, Norman died. Olga’s health began to fail also, and she died at Lorneville, near Invercargill, on 1 July 1989. She was survived by her three children.
Olga Sansom’s contribution to natural science had been recognised by the Southland branch of the Royal Society of New Zealand in 1960 when it made her a life member. The Southland Museum and Art Gallery similarly honoured her in 1966. In 1973 her achievements gained international attention when she was included in the first edition of The world who’s who of women. Her services to New Zealand were acknowledged in 1979 when she received the Queen’s Service Medal.