Collaborative Research: BEST SYNTHESIS: The variable transport of pollock eggs and larvae over the Bering shelf: A marriage of physics and biology.

University Of Alaska Fairbanks Campus, Fairbanks AK

Investigators

Abstract

The recent Bering Sea Ecosystem Study (BEST) program and its partner the Bering Sea Integrated Ecosystem Research Program (BSIERP) have resulted in a better understanding of the roles of temperature and stratification in regulating the walleye pollock population, but the role of advection remains poorly understood. Therefore, funds are provided to elucidate how the ocean?s response to variable atmospheric forcing affects the distribution of walleye pollock (Theragra chalcogramma) eggs and larvae on the eastern Bering Sea shelf. The proposed approach builds on advances made under the BEST-BSIERP program and will use a combination of new modeling results and recent observations to examine historical dispersal pathways of pollock eggs and larvae and will simulate how these might change in the future under various scenarios. Advection, the transport of material or a property by the movement of a fluid, plays a major role in the life cycle of many fish populations because early life history stages depend on quasi-passive transport from spawning areas to suitable nursery grounds. Drift trajectories of eggs and larvae and the physical and biological conditions they encounter during the first few months after spawning are highly variable and are linked to regional and broad-scale climate conditions. Thus atmospheric and oceanographic variability affects the survival of early life stages and the resulting year class strength of fish populations, such as walleye Pollock, on the eastern Bering shelf. The results of this project will improve our understanding of the interactions of physical and biological processes on walleye Pollock and, consequently, lead to better management of this important fishery.