Keppel Harcourt Barnard, zoologist and museum director, was the son of Harcourt George Barnard, solicitor, and his wife Anne Elizabeth, borne Porter. He attended a private school in Camberley, near London, where he showed his interest in natural history by winning a prize for an essay and collection of insects. Subsequently he was sent to the Realschule in Mannheim, Germany, where he learned German. Returning to England he entered Christ's College, University of Cambridge, where he studied botany, geology and zoology and was awarded the degree Bachelor of Arts (BA) in 1908. Afterwards he studid law and was called to the Bar of the Middle Temple in 1911. The degree Master of Arts was awarded to him in absentia in 1913.
Barnard was more interested in science than in law and spent two terms as an honorary naturalist at the Marine Biological Laboratory in Plymouth. In 1911 he came to South Africa to accept the post of assistant in marine biology at the South African Museum in Cape Town. There he remained for the rest of his life and was the sole member of the marine biological staff for 45 years. However, his appointment has been described as "the major event in the history of South African marine taxonomy" (Brown, 1999, p. 23). He worked mainly on the marine collections of the museum and those made by the marine biologist J.D.F. Gilchrist*, and on specimens he collected himself. He was an avid collector and his collecting expeditions took him, among others, to the coast of Mozambique (1912); the coast (1913) and interior (1917) of KwaZulu-Natal; Ovamboland and the Kaokoveld up to the Kunene River (1921, 1923 and 1926) as part of the Zoological Survey of South West Africa (now Namibia) during which he also collected plants; and Gordonia and the Orange River down to the Augrabies Falls (1925). Most of his specimens, including the plants, were kept in the South African Museum.
The results of his investigations were reported in over 200 publications, most dealing with taxonomy, including a thesis, The Distribution of Crustacea in South African waters, on the basis of which the University of Cape Town awarded him the degree Doctor of Science (DSc) in zoology in 1924. He produced three major monographs, namely A monograph of the marine fishes of South Africa (1925-1927, 1065 pp), being the first comprehensive work of its kind and including some 1000 species; Descriptive catalogue of South African decapod Crustacea (1950, 837 pp), dealing with some 800 species of crabs and shrimps; and Contributions to the knowledge of South African marine Mollusca (in five parts, 1958-1964, with two further parts published posthumously in 1969 and 1974). His papers included a series of twelve titled "Contributions to the Crustacean fauna of South Africa" in the Annals of the South African Museum (1914-1940), a number of "Contributions to a knowledge of the fauna of South West Africa" in the same journal, and reports on the amphipod crustaceans collected by various international expeditions. He revised the freshwater fishes of the Western Cape and described several new species in 1938 and 1943. Nearly all his research dealt with marine and freshwater fauna and his papers included authorotative accounts on several groups of insects with aquatic nymphs or larvae, including the Ephemeroptera (mayflies), Megaloptera (alderflies), Trichoptera (caddis flies), Plecoptera, (stoneflies), and Odonata (dragonflies and damselflies). Several of these papers were published in the Transactions of the Royal Society of South Africa between 1925 and 1934. In addition he published three semi-popular books on marine life: A pictorial guide to South African fishes (1947), A beginners guide to South African shells (1951), and South African shore life (1954).
In 1921 Barnard was promoted to assistant director of the South African Museum, serving as acting director in 1924. When Dr Leonard Gill retired as director in 1942 Barnard was appointed as acting director, and in 1946, after World War II, as director of the museum, a post he held until his retirement in 1956. After his retiremen he was appointed honorary keeper of fishes and marine invertebrates and continued his research on South African marine Mollusca with an honorarium from the museum and a bursary from the Council for Scientific and Industrial Research.
Barnard was a keen mountaineer who climbed in various South African mountain regions as well as in the Alps. His discovery on Table Mountain of Phreatoicus, an Australian genus of primitive Crustacea, led to his intensive study of the mountain fauna of the Western Cape. In 1913 he joined the Mountain Club of South Africa and from 1918 to 1945 served as its honorary secretary. In 1928, in the Annual of the Mountain Club of South Africa, he described his fruitless search for the northern survey beacon erected by Abbe N.L. De la Caille* in 1751. Other historical articles by him dealt with William Mann* (1943, 1948), Sir John Herschell* (1954) and the bibliographical details of some early publications of scientific interest. During these years he donated various historical documents to the South African Library.
In the course of his career Barnard contributed to the activities of several scientific societies. He served on the council of the South African Geographical Society from 1919 to 1940, represented the society at the International Geographical Congress at Cambridge in 1928, was joint vice-president from 1932, and president of the society for 1935-1936. In his presidential address, "Geographical zoology", and an earlier paper on "Isolated fauna" (Journal of the Geographical Society of South Africa, 1927) he reported some of the results of his investigation of the mountain fauna of the Western Cape. He was a member of the Conchological Society of South Africa, serving as its president for 1962-1963, and was a member of council of the Royal Society of South Africa from 1923. He served on the first committee of the Cape Natural History Club in 1922 and as president in 1923 and 1930/1. During the compilation of the International Catalogue of Scientific Literature (1901-1914) by the Royal Society of London he was for some time local secretary for the project. At the time of his death he was a member of the Table Mountain Preservation Board.
Barnard has been described as "one of the most prolific and probably the widest-ranging taxonomist in history" (Griffiths, 1999, p. 45), and "a modest yet towering figure in 20th century marine biology" (Kilburn, 1999, p. 38). He became the leading marine taxonomist in southern Africa, the authority on local fishes, an international authority on Crustacea, and his studies of these groups and the molluscs contributed much to knowledge at the time. A number of species were named after him, including both marine and non-marine molluscs. He was a brilliant scientist, an accurate observer, an enthusiastic, diligent and painstaking worker who set high standards for himself and others, but a great critic of slipshod thought and careless writing. As a person he was shy, very modest, and reserved about his own professional success. His extreme intellectual reserve made him a poor lecturer and prevented him from delivering papers in public. Nonetheless his achievements were widely recognised, both locally and internationally, for example, he was elected a Fellow of the Linnean Society of London, was elected a Fellow of the Royal Society of South Africa in 1920 and an Honorary Fellow in 1956, and an honorary member of the Cape Natural History Club in 1922. He received the Gold Badge of the Mountain Club of South Africa (1924), was awarded the King George V Silver Jubilee Medal (1935), the Queen Elizabeth II Coronation Medal (1953), the Senior Captain Scott Memorial Medal of the South African Biological Society (1936), and the South Africa Medal (Gold) of the South African Association for the Advancement of Science (1945). In 1956 the University of Stellenbosch awarded him an honorary Doctor of Science degree.
In 1915 he married Alice Watkins, with whom he had a son and a daughter.