THE DEVELOPMENT OF RECRUITMENT FISHERIES OCEANOGRAPHY IN THE UNITED-STATES

Recruitment fisheries oceanography studies the impact of the environme nt on the annual production of young to fished populations (finfish as well as invertebrates). Interannual variation in recruitment is the m ost important source of biological variability facing fisheries manage rs. Because most variation in recruitment occurs during early, mainly planktonic stages, recruitment fisheries oceanography usually integrat es studies of plankton and physical oceanography. The concepts upon wh ich these studies rest were first expressed in the late 1800s by Spenc er Fullerton Baird, the first Commissioner of the US Commission of Fis h and Fisheries. These concepts appear to have been independently deve loped by Johan Hjort and others in northern Europe in the early 1900s, and brought back to the United States through contacts between Hjort and Henry Bryant Bigelow, who passed the ideas to his students at Harv ard University, including Lionel Albert Walford and Oscar Elton Sette. Although both Walford and Sette did their initial work in recruitment fisheries oceanography off the US east coast, as federal fisheries sc ientists, they were sent to California in response to the decline of t he sardine fishery, where they incorporated the ideas of Hjort into th e programme that has become the California Cooperative Oceanic Fisheri es Investigations (CalCOFI). The original plan for CalCOFI research wa s to provide a test: of Hjort's ideas. Scientists working with CalCOFI implemented this plan and conducted subsequent research that had its roots in the ideas expressed by Baird. This research was in marked con trast to the fishery-yield orientation of most fisheries research that was being conducted at the time on the west coast of North America, u nder the dominating influence of William Francis Thomyson. In recent y ears, federal fisheries programmes have investigated recruitment proce sses of a number of other fish stocks, and considerable effort has bee n expended toward refining the conceptual framework beyond the hypothe ses of Hjort. This paper expands on this history, making note of scien tists who were particularly important in the evolution of this discipl ine. We conclude that although recruitment fisheries oceanography has become a well-established field of study, and many technological advan ces have been made, the recruitment process is still not well understo od and fluctuations in year-class abundance remain a major source of u ncertainty in managing marine fisheries.