Photo Credit: Michael Sigler

About the Project

Background

More than 50 scientists from 11 institutions are taking part in the $17.6 million Gulf of Alaska ecosystem study that examines the physical and biological mechanisms that determine the survival of juvenile groundfishes in the Gulf of Alaska. From 2010 to 2014, oceanographers, fisheries biologists and modelers studied the gauntlet faced by commercially and ecologically important groundfishes, specifically walleye pollock, Pacific cod, Pacific ocean perch, sablefish and arrowtooth flounder, during their first year of life as these fish are transported from offshore areas where they are spawned to nearshore nursery areas. A total of $9.6 million was provided by the North Pacific Research Board and substantial in-kind support was provided by participating agencies, including National Oceanic and Atmospheric Administration (Alaska Fisheries Science Center and Pacific Marine Environmental Laboratory), U.S. Fish and Wildlife Service, and U.S. Geological Survey.

Synthesis

A synthesis was initiated in September 2015 and it will continue through February 2018. The synthesis is building upon the results of the field program and producing products that apply the results to fisheries management.

The Gulf of Alaska is teeming with life and supports some of the most productive fisheries in the United States. The strongest currents found along the coasts of North America flow through the Gulf of Alaska, dispersing marine life and nutrients from deeper waters across the continental shelf.  Bays and estuaries represent important nursery habitats for young fishes, and feeding grounds for seabirds and marine mammals.  This multi-disciplinary project is examining the oceanography, biology, and ecology of the Gulf of Alaska in an effort to better understand how the environment influences fish survival, and ultimately the success of fisheries in the Gulf of Alaska.  For more background on the Gulf of Alaska, see the Implementation Plan that was used to develop this project.

Implementation Plan

What We Are Studying

The Gulf of Alaska Project tests three main hypotheses about the survival and recruitment of five focal groundfish species, (walleye pollock, Pacific cod, Pacific ocean perch, sablefish and arrowtooth flounder), and the gauntlet they face as they move from offshore spawning areas to nearshore nursery areas during their first year of life. Recruitment is the addition of individuals to a population and is critical for the sustainability of fish populations and commercial fisheries.

Photo Credit: Tom Helser

The Gauntlet

The primary determinant of year-class strength for marine groundfishes in the Gulf of Alaska is early life survival. This is regulated in space and time by climate-driven variability in a biophysical gauntlet comprising offshore and nearshore habitat quality, larval and juvenile transport, and settlement into suitable demersal habitat.

Photo Credit: Melissa S. Armstrong

Regional Comparisons

The physical and biological mechanisms that determine annual survival of juvenile groundfishes and forage fishes differ in the eastern and western GOA regions.

Photo Credit: John Matzick

Interactions

Interactions among species (including predation and competition) are influenced by the abundance and distribution of individual species and by their habitat requirements, which vary with life stage and season.

Major Objectives

Nine main objectives of Gulf of Alaska Project have been identified that will contribute to addressing the overarching hypotheses. They range from better understanding oceanographic processes, to examining fish distributions, habitat associations, and growth rates, and building a system of linked models to describe the ecological connections that affect fish survival. Click on the objectives below to learn more.

Objective 1

Quantify the importance, timing and magnitude of the climactic and oceanographic mechanisms that control ocean conditions in the eastern and western Gulf of Alaska regions.

Objective 2

Determine how physical and biological mechanisms influence the distribution, timing, and magnitude of primary and secondary productivity in nearshore, inshore, and offshore areas of the eastern and western Gulf of Alaska regions.

Objective 3

Provide a synoptic view, from the shoreline out to beyond the shelf-break, of the distribution and abundance of forage fishes and the early life stages of five focal groundfish species.

Objective 4

Use a comparative approach to assess spatial and temporal variability in the ecosystem, primarily between the eastern and western Gulf of Alaska regions among spring, summer, and fall.

Objective 5

Analyze habitat associations, create habitat suitability maps, and use that information to study the influence of habitat requirements on the spatial overlap among species and resulting predation and competition.

Objective 6

Use multiple techniques to analyze the diets of species from different trophic levels and use these data to elucidate trophic relationships.

Objective 7

Assess nutritional condition and determine rates of growth and consumption to determine how physical and biological factors influence the physiological ecology of the focal fish species.

Objective 8

Use historical datasets to analyze temporal variability in potential climatic, oceanographic, or biological drivers influencing the early life survival of key groundfish species.

Objective 9

Build a system of linked models that describe the connections among climate, oceanography, primary and secondary productivity, and the early life survival of the focal fish species.

Photo Credit: William McCrossan

Study Regions

The sampling stations for the Gulf of Alaska Project are illustrated on the series of maps below. The project will make regional comparisons between the central and eastern Gulf of Alaska. In the central Gulf of Alaska, the continental shelf is broad, with high demersal fish biomass but low species diversity. In the eastern Gulf of Alaska, the continental shelf is narrow and biomass is lower, but species diversity is higher.

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Integrated ecosystem research projects are ambitious, requiring collaboration from experts in various disciplines of marine biology and oceanography, and cooperation with data managers, vessel crew, marine educators, and support staff. Over 45 researchers were involved in GOAIERP, and with the help of Axiom Data Science, they shared data with one another and made advances in multi-disciplinary science.  Given the large size of the team and the variety of disciplines involved, GOAIERP also required careful program leadership from the Gulf of Alaska Board of Investigators (GABI) and NPRB staff. 

Meet the Team

Photo Credit: David Barbee

Communications Plan

A formal communications plan for the final products of the Gulf of Alaska Project is under development.  We have been communicating preliminary results in a variety of ways, including annual presentations at scientific conferences such as the Alaska Marine Science Symposium, Western Groundfish Conference, and Americal Fisheries Society meetings.  We talk with the general public at Sitka WhaleFest each year, among other events.

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Program History

In September 2008, NPRB released a request for pre-proposals to begin the process of developing an integrated ecosystem research program focused on the Gulf of Alaska. Pre-proposals were requested to address how environmental and anthropogenic processes, including climate change, affect various trophic levels and dynamical linkages. A formal request for proposals (RFP) was issued upon pre-proposal review.

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