Gerald Augustus Harold Bedford studied entomology at the South Eastern Agricultural College at Wye, Kent. Afterwards he worked under Professor F.V. Theobald at the British Museum (Natural History) until early in 1912, during which time he began to acquire his very extensive knowledge of the Culicinae, a subfamily of the mosquitoes (Fam. Culicidae). Around this time he was elected a Fellow of the Entomological Society of London. Also at about this time Dr Arnold Theiler*, director of the Onderstepoort Veterinary Research Laboratories, asked Professor Theobald to recommend an entomologist for employment at Onderstepoort to assist in the study of horsesickness and other insect-borne diseases of livestock. Bedford was recommended and assumed duty in February 1912 on a three year contract. Later he was appointed to the permanent staff as a research officer, a position he held up to the time of his death.
During the earlier years of his appointment Bedford investigated almost all the species of mosquitoes occurring in South Africa in an attempt to discover the vector of horsesickness, but without success. Subsequently he became one of the foremost systematists in South African entomology, who contributed much to knowledge of the local parasitic insect fauna. Most of his work was published in the series of Reports of the Director of Veterinary Research (the title varies) from 1912 to 1932 and its successor, the Onderstepoort Journal of Veterinary Science (from 1933). His last two papers appeared posthumously in 1939. He studied practically all the parasitic orders of arthropods that occur upon the domestic animals and the rest of the South African large vertebrate fauna; made a painstaking study of the life cycle of the sheep scab mite, described in "Experiments and observations carried out with Psoroptes communis at Onderstepoort" (Third and Fourth Reports of the Director of Veterinary Research, 1915, pp. 99-113); and compiled an extensive "Check list and host list of the external parasites found on South African Mammalia, Aves and Reptilia" (Eleventh and Twelfth Reports of the Director of Veterinary Education and Research, 1926, pp. 703-818). Later he specialised in the suborder Anoplura (the so-called "suckling lice") on which he became one of the foremost authorities. At the time of his death he was working on a monograph dealing with the South African ticks.
Bedford was a member of the Transvaal Biological Society and read four entomological papers at its meetings during 1913-1916. In the latter year he became a founding member of its successor, the South African Biological Society, and published two papers on South African ticks in its South African Journal of Natural History (1924, 1925). In 1915 he became a member of the South African Association for the Advancement of Science and in 1932-3 was a member of its council. He attended meetings of the Pretoria Entomological Club (1933-1936) and shortly before his death attended the inaugural meeting of the Entomological Society of Southern Africa on 14 October 1937.
Bedford married Lydia Marie Santo-Brown, but they were divorced in 1934.