William Roy McGregor was born in Thames on 8 July 1894, the son of Peter McGregor, a draper, and his wife, Susan Melville Rea. He attended Auckland Grammar School in 1909, then – it is understood – briefly took up schoolteaching. In 1918 he became a demonstrator in biology at Auckland University College, and in 1922 was appointed a lecturer in zoology. He married Kathleen Gladys Dacey on 24 August 1920 at Ponsonby; they were to have three daughters and a son.
In the late 1920s McGregor doubled as a lecturer in the college's short-lived School of Forestry. Around this time he was also contracted as consultant to the State Forest Service at Waipoua. By the time he finally graduated BSc in 1932, the somewhat dilettante Professor J. C. Sperrin-Johnston had retired and McGregor was already carrying much of the responsibility for zoology. In 1933 the Biology Department was divided, with McGregor as lecturer in charge of zoology, later with one junior assistant.
By 1939 the Zoology Department was set up in the fine, spacious, R. A. Lippincott-designed building that McGregor had used some political skill to secure. Internally planned and furnished by him, the new department was run as cleanly, efficiently and autocratically as a ship of the line. McGregor is remembered as a powerful figure, black-gowned and Roman-profiled. The sobriquet 'Barney' was irreverent: with his formal style and utterance he had never – it was said – quite mastered the vernacular.
McGregor was to single-handedly create New Zealand's best university zoology museum. Built around collections from his self-financed expedition in 1929 to Australia, New Guinea and the Dutch East Indies (Indonesia), it was enriched with dissections, models and a fine range of bones. Up to the 1950s McGregor gave virtually all the lectures. After a strong first year designed for medical students, the course moved into traditional comparative morphology, treating vertebrates and invertebrates year and year about. Meticulous and thorough, he dictated his lectures in an orotund, old-fashioned style. Fieldwork or live material was unheard of. But the reading for the master's degree, in evolution and embryology, was absorbing and up to date. Many of the masters graduates were to attain high posts in zoology; and in a wider world few were critical of their early grounding.
Over a 20-year span a legendary controversy, known as the 'McGregor affair', intensified. Its genesis lay in McGregor's firm conviction that a former college president, Sir George Fowlds, had encouraged him to expect a professorial chair if he succeeded in building a strong teaching department. The university later resisted this, citing his mere bachelor degree and want of published research – not unknown among professors of that day. Having accepted under protest the title of associate professor in 1949, McGregor in 1959 was to petition Parliament for redress and compensation. A committee reported unanimously in his favour, but left the necessary response to the University of Auckland. Nothing was forthcoming.
His battle from the mid 1940s for sanctuary status for the Waipoua kauri forest, which he knew intimately, was more successful. With its John Ruskin-styled prose and fine glass-plate photography, his pamphlet The Waipoua forest (1948) was an early effective conservation manifesto.
Kathleen McGregor died in November 1954 and on 27 October 1955 at Auckland William married Elvina Margaret Diederich. After his retirement in 1960, McGregor mellowed but did not put controversy aside, campaigning against the milling of kauri in the Warawara Forest, Northland. He also founded the New Zealand Conservation Society, visited English universities, and planned a work on the British naturalist and explorer Alfred Russel Wallace, whom he admired greatly. He died at Auckland on 1 June 1977 survived by his wife and the children from his first marriage. A forest giant that he had discovered at Waipoua was aptly named the 'McGregor Kauri'.
From his years of sway, old associates remember 'Barney' McGregor as hard on himself and often arbitrary or suspicious with others. But his wider judgements could be perceptive and kind, and his encouragement was worth more for not coming easily. Sadly, he seemed to turn away much of the regard he had the power to inspire. Professorial in all but title, he served zoology in his day better than was often realised.