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Bering Sea FOCI was active from 1991 through 1997.  For a detailed summary of BS FOCI, see the Final Report ( PDF).

An Overview of Bering Sea FOCI

GOAL - The objective of Bering Sea FOCI was to understand the effects of the physical and biological environment on recruitment of walleye pollock in the southeastern Bering Sea. Because of its rich abundance of fish, the Bering Sea has been the focus of much international fisheries research. Although interpretation of fishery data varies sometimes with political need, a case can be made for a counterclockwise movement of pollock with life stage. Eggs are predominantly spawned along the southern and eastern slopes and basins of the Bering Sea, hatch into larvae along the eastern and northeastern slopes, and develop into juveniles that may be found predominantly on the western slope and shelf along the Russian coast. One component of FOCI research defined the basin-wide ocean circulation and characteristics of various pollock populations. The second component considered the contrast in characteristics between the oceanic and shelf domains. Previous research (e.g., PROBES) indicated that the basin and the shelf are biologically separate domains with different likelihoods of pollock survival. In FY 1994, Bering Sea FOCI began focus on the eastern Bering Sea, examining the ocean circulation, the food supply, predators, egg and larval transport, biological rates, and other criteria for the basin and shelf environments. FY 1997 was the final year of funding for Bering Sea FOCI.

OPERATIONS AND RESOURCES - The program had a core of principal investigators at the Alaska Fisheries Science Center (AFSC) and the Pacific Marine Environmental Laboratory (PMEL), both in Seattle, Washington, and a number of investigators from academic institutions across the nation. Principal leadership was supplied by Gary Stauffer/AFSC and Jim Overland/PMEL. Scientific guidance was furnished by Jim Schumacher/PMEL, Art Kendall/AFSC and Jeff Napp/AFSC. Allen Macklin/PMEL served as program coordinator. Two NOAA research vessels, Miller Freeman and Surveyor, provided working platforms in the Bering Sea during late winter, spring, and fall.

Work proceeded in the laboratory and in the field according to research plans developed by the program's principal investigators and reviewed by an external committee of senior scientists. Broad areas addressed were pollock populations, distributions of phytoplankton, ichthyoplankton, pollock eggs and larvae, juveniles, oceanography, and fisheries oceanography.

COLLABORATION - Bering Sea FOCI shares its information freely with other research projects of NOAA's Coastal Ocean Program, with Shelikof Strait FOCI, and with the academic community. An important operational goal of Bering Sea FOCI was to provide information to the North Pacific Fisheries Management Council to help manage the pollock resource.

SAMPLE RESULT - Dennis Powers, Stanford University, conducted genetics studies on walleye pollock of the North Pacific. Understanding from such studies enables fisheries biologists to distinguish between stocks, determine relative contributions of stocks to the fishery, and evaluate the impact of fishing pressure on those stocks. Samples were collected from both sides of the North Pacific Ocean: Gulf of Alaska, Aleutian Islands, Bering Sea, Kamchatka Peninsula and Japan. Powers used two approaches to discern differences in genetic structure of pollock, indicating their relative "genetic closeness" as separate populations. The first method analyzed mitochondrial DNA, the second examined specfic microsatellite loci.

The analysis of mitochonrial DNA in 164 individuals detected a small, but significant difference between fishes from Asian waters, and those from the western Bering Sea and the Gulf of Alaska (Figure 1).


The microsatellite loci showed a significant difference between eastern Bering Sea and western Bering Sea fishes (sample size=221). In addition, they also showed a significant difference between the Gulf of Alaska samples and those from the Bering Sea (Figure 2). One of the loci, Tch 2, shows a null, or non-amplifying, allele in the eastern Bering Sea samples. Characterization of the polymorphism causing this null may itself be informative about population structure in pollock.


Figure 3 shows the origins (2, 3, 5, 6, 7, 8) of samples used for the microsatellite part of the study.


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