The critical first year of life of walleye pollock (Gadus chalcogrammus) in the eastern Bering Sea: Implications for recruitment and future research

Abstract

Walleye pollock (Gadus chalcogrammus) support a large commercial fishery in the eastern Bering Sea despite large interannual and decadal swings in population abundance. These oscillations challenge the fishery, prompting significant effort directed to understanding the species and its recruitment. Conceptual paradigms of walleye pollock recruitment recognize that understanding the factors affecting survivorship during the first year of life is central to understanding population fluctuation. Since the first year is critical to year-class strength of this key economically and ecologically important species, we review the state of knowledge of pre-recruit walleye pollock ecology in the eastern Bering Sea during this critical first-year period, including spawning, changes in vertical and horizontal distributions, feeding, growth, body condition, transport, and predation. We then critically examine the recruitment paradigms based on the component processes that have been proposed to explain mechanisms of recruitment control. We identify paradigm strengths or weaknesses relative to our current state of knowledge, discussing relevance and validity. Finally, we identify gaps in knowledge and propose areas of future research effort.