Karel Hendrik Voous, former Curator and Deputy Director of the Zoological Museum of the University of Amsterdam (now the Institute of Taxonomic Zoology) and former professor of Systematic Zoology and Zoogeography at the Free (Protestant) University in Amsterdam, Secretary General of the 15th International Ornithological Congress (IOC), a longtime editor of Ardea and Limosa, and the dean of Dutch ornithologists, died on 31 January 2002 in Huizen, The Netherlands. He was 82 years old.
Voous became a member of the AOU in 1966 and an Honorary Fellow in 1969. He was an honorary member or corresponding member of another ten ornithological or conservation societies, including the Netherlands Ornithologists' Union and the British Ornithologists' Union, which in addition awarded him its prestigious Union Medal in 1975. For decades, Karel Voous played a crucial role in the organization of the International Ornithological Congresses, as a member of its International Committee from 1950 to 1982, of its Executive Committee from 1970 to 1974, and of its Standing Committees on Ornithological Nomenclature and For the Coordination of Seabird Research. In 1970 he was Secretary General of the 15th IOC in The Hague, and edited its 745-page Proceedings. He was elected Honorary President of the 1994 IOC in Vienna.
Karel Voous was born in Huizen, North Holland, on 23 June 1920. He said that his interest in birds started when, as a boy of five or so, he tried to catch House Sparrows at his parents' house in Amsterdam by putting salt on their tail. Voous pursued academic studies in biology at the University of Amsterdam from 1938 to 1947. He became a student assistant at the Zoological Museum there in 1940, and was subsequently promoted to curator of ornithology and, from 1950 to 1963, to deputy director. In 1947, Voous defended his Ph.D. thesis, a fundamental paper on the biogeography of the genus Dendrocopos (published in Limosa the same year), written under the supervision of Professor Lieven F. de Beaufort. Voous's memorial of de Beaufort the ornithologist, biogeographer, and Huguenot (Ardea 1968; in Dutch) is a moving and personal tribute to a man who played a pivotal role in his career. Although, by his own admission, Voous did not much enjoy teaching, he was appointed adjunct professor of zoogeography at the Free University of Amsterdam in 1955, a position he held until 1963. In 1964, he became full professor there, and retained that position until his early retirement in 1975, when he was only 55.
Voous's ornithological interests were diverse. First, and perhaps closest to his heart, the avi-fauna of his native country fascinated him. He published numerous papers and notes on the distribution, breeding biology, and behavior of birds in Holland, culminating in his being senior author, in 1970, of the check-list of birds in that country, Avifauna van Nederland. In 1995, he wrote In de Ban van Vogels (“Under the spell of birds”), a 605-page history of ornithology in Holland, including a short biography of Dutch ornithologists and the history of the Netherlands Ornithologists' Union. He also authored a neat field guide (text in Dutch with extensive English summaries) to the birds of the Netherlands Antilles in 1955. But Voous was also keenly interested in worldwide problems of geographic distribution, speciation, and biogeography. Alone, or in co-authorship with others, especially his friend J. G. van Marle, he published papers on those topics in genera such as Dryocopus, Sitta, Ceyx, Coracina, Buteo, Tyto, Ciccaba, Strix, Larus, and Sterna. Pelagic birds, their biology and distribution, was another of his interests. His papers on speciation in the fulmars and on migration of the Greater Shearwater are classics. The complex problems posed by the evolution of faunas intrigued Voous. To better understand them, he devised a system of faunal elements that he later applied to the birds of the western Palearctic in his pioneering Atlas of European Birds, published simultaneously in Dutch, English, and German in 1970. The meticulous work he carried out to prepare that volume led Voous to propose, in 1977, a List of Holarctic Bird Species, which has been widely accepted by amateurs and professionals alike. It was adopted, for example, by Stanley Cramp in his Handbook of the Birds of Europe, the Middle East and North Africa: The Birds of the Western Palearctic (1977–1994), for which Voous was a member of the editorial team.
After his formal retirement in 1975, Voous actively continued work on various projects. One of those resulted in his book Owls of the Northern Hemisphere in 1988. Curiously, given that he was a professional ornithologist, Voous considered his longstanding studies of owl biology to be one of his hobbies, the others being portrait photography, biographies, and what he called “theology” (but which I would describe as an interest in the relationships between science and religion, a topic about which he published several papers in Dutch). Voous was also concerned with aid programs in developing countries.
Even though he was a reserved person and kept his knowledge partially hidden behind a somewhat formal façade, Voous was a tremendous force in European and world ornithology. In part because he was a meticulous worker and thinker, his opinions were always fair and highly respected. His taste for precision and scholarship could not have been better used than during the many years he served as editor of Ardea and Limosa. During his editorship of Ardea, in particular, he transformed that journal from a rather local to a world-class publication. Although I did not have a chance to get to know Voous as closely as I did some other great figures of 20th-century European ornithology, my warm appreciation of him stems from his careful approach to biological problems, the great respect he showed for the work of others, his profound involvement in the international ornithological community, and his lack of intellectual rigidity, illustrated by his ability to admit to doubt in solving bio-geographic puzzles or understanding difficult systematic questions.