Resource Ecology and Fisheries Management quarterly research reports for Jul-Sept 1998 for the Alaska Fisheries Science Center

Age and Growth Program

Estimated releases of production ages for January to September 1998 were 789 flathead sole; 336 rock sole; 566 Dover sole; 466 yellowfin sole; 660 arrowtooth flounder; 7,345 walleye pollock; 1,936 sablefish; 563 Atka mackerel; 1,760 Pacific whiting; and 780 Pacific ocean perch for a total of 15,201 samples. Also, 4,598 were tested; 2,562 were updated; and 300 were examined and determined to be unreadable.

By Dan Kimura.

Resource Ecology and Ecosystems Modeling

A total of 6,830 fish stomachs were collected for the eastern Bering Sea, 693 for the Gulf of Alaska, and 4,948 for the Washington-Oregon-California region. Laboratory analysis was performed on 1,573 stomachs from the Bering Sea and 423 from the Aleutian Islands region. Five observers were trained to collect stomachs.

Our main opportunity for collection of groundfish stomach samples is through the echo-integration/trawl surveys and bottom trawl surveys of the RACE Division. This quarter, the Resource Ecology and Ecosystem Modeling Program participated in the RACE Division bottom trawl surveys of the Washington-Oregon-California shelf and the eastern Bering Sea to collect samples from dominant groundfish species in those areas. In addition, we participated in the ADF&G seasonal bottom trawl survey of the Kodiak shelf region to collect samples.

Bering Sea ecosystem research communication and coordination is ongoing. The second interagency Bering Sea workshop held this past June in Anchorage provided new research perspectives from a broader scientific and constituent audience. The comments and perspectives presented have been summarized in a workshop proceedings and a revised Bering Sea ecosystem research plan. Both documents are now available on the World Wide Web and can be viewed from the AFSC website at:
http://www.refm.noaa.gov/reem/
or from NOAA’s Bering Sea Theme Page:
http://www.pmel.noaa.gov/bering/pages/inter-agency/

Cooperative work on predator-prey interactions with the U.S. Fish and Wildlife Service, Alaska Maritime Wildlife Refuge (USFWS/AMWR) has recently begun. Investigators from the USFWS/AMWR have a program for obtaining stomach samples of groundfish predators in important bird foraging areas in the Gulf of Alaska and eastern Bering Sea using longlines or landed-commercial or charter-boat catches, including some of the sites that are part of the Seabird, Marine Mammal, Oceanography Coordinated Investigations (SMMOCI). Investigators hope to learn more about food webs and forage fish abundance and utilization in bird foraging areas. Task personnel are now receiving those groundfish stomach samples and performing laboratory and data analysis on them. These samples should enhance the existing groundfish food habits data base maintained by our task by providing more information about inshore food webs.

Troy Buckley is collaborating with Jerry Hoff (RACE Division) and Jeff Drazen, a doctoral student at Scripps Institution of Oceanography, to study the feeding ecology of several species of grenadiers - giant (Albatrossia pectoralis) and Pacific (Coryphaenoides acrolepis), popeye (C. cinereus), smooth (Nezumia liolepis), and California (N. stelgidolepis). From the eastern Pacific Ocean, the stomach contents of only a few giant and Pacific grenadier have been described and the food habits of the other species have not previously been examined. The majority of our stomach samples were collected during the 1997 groundfish survey of the West Coast upper continental slope. Additional samples are being collected by Jeff Drazen using specially designed traps. Laboratory analysis is proceeding and several papers summarizing the results are planned.

By Patricia Livingston.

STATUS OF STOCKS AND MULTISPECIES ASSESSMENTS

Feasibility Study of Using a Single Beam Seabed Classification System to Identify and Quantify Slope Rockfish Habitats in the Gulf of Alaska

Since rockfish tend to exhibit preference for particular habitats, precision in abundance estimates could be significantly improved by implementing survey designs that are stratified by bottom type. However, doing this requires information about both the distribution and quantity of habitat in the survey area. Our study explored the use of an acoustic single beam system known as the QTC View to acquire such data. The objective of the study was to assess QTC View’s classification performance in general, with the specific aim of determining the feasibility of its use to identify and quantify slope rockfish habitat in the Gulf of Alaska. It was of particular interest to determine its limitations with respect to operational parameters such as ship speed, slope, and depth. In addition, to address the logistical feasibility of using the QTC View to quantify fish habitat in an area as vast as the continental slope of the Gulf of Alaska, a line-intercept study based on the substrate heterogeneity was carried out to determine the transect spacing needed for a given level of precision in the estimates.

Field work was conducted in Southeast Alaska aboard the NOAA research vessel John N. Cobb during 11 - 20 August 1997. Analysis of the results of the field work indicated that vessel speeds between 3 and 12 knots did not significantly impact the consistency with which the QTC View classified the seabed, and depths of at least 220 m did not adversely affect QTC View’s classification performance. However, slope gradient apparently had a major impact on classification accuracy. Out of 18 validation sites, the QTC View classified 14 accurately, and all of the 4 incorrectly classified sites were associated with relatively steep slopes. The maximum operational slope was estimated to be between 5 and 8 degrees.

Using line intercept theory, the spacing requirements between parallel transects of a survey in an area as diverse as the continental slope of the Gulf of Alaska were highly dependent on the desired level of detail. In the extreme case where the amount of all acoustically distinct bottom types are to be estimated with a coefficient of variation (CV) of 0.1, the spacings between transects cannot be greater than approximately 230 m, implying over 3,000 hours of ship time to cover the entire continental slope of the Gulf of Alaska between Ketchikan and King Cove. Considerably greater transects spacings (and time savings) are possible if two or more bottom types are combined into a single “habitat category” and if higher CVs are acceptable.

In conclusion, due to its limitations in areas of steep slope, the QTC View is not likely to be an effective tool for quantifying slope rockfish habitat. It should, however, be an excellent tool for identifying and quantifying many other fish habitats that are found over relatively flat bottoms. The study was completed by Paul von Szalay, University of Washington graduate student, under the auspices of the AFSC’s Rockfish Working Group.

By Daniel Ito.

Socioeconomic Assessment Program

The Task has been heavily involved in activities in support of the Pacific and North Pacific Fishery Management Councils (PFMC and NPFMC) and other cooperative efforts within the Agency and beyond.

U.S. Groundfish Observer Program

One hundred and ninety-one observers were trained, briefed, and equipped for deployment to fishing and processing vessels and shoreside plants in the Gulf of Alaska and Bering Sea during the third quarter of 1998. Thirty-one of the observers were briefed in Seattle at the AFSC Observer Program, 12 in Dutch Harbor and Kodiak at the Observer Program’s field offices, and 87 in Anchorage at the University of Alaska (UAA) observer training center. Another four were excused from briefing because they had just completed a debriefing and were returning immediately to the field on another contract. In addition, 35 first-time observers were trained by the UAA, and 22 were trained in Seattle.

During the third quarter of 1998, observers sampled aboard 198 fishing and processing vessels and at 15 shoreside processing plants. Seventy percent of the observers hired in the third quarter had previous domestic observer experience.

The Observer Program conducted a total of 71 debriefings during the third quarter of 1998. Fourteen debriefings were held in Dutch Harbor and Kodiak, and 57 were held in Seattle.

At its June 1998 meeting, the NPFMC received notification from NMFS and the Pacific States Marine Fisheries Commission (PSMFC) that the third-party, joint partnership agreement (JPA) Observer Program structure would not be implemented. This Observer Program structure would have established the PSMFC as the sole source through which the fishing industry would obtain observers, thus correcting the problem of perceived conflict of interest between the fishing industry and the observer contracting companies. Because of unresolved legal issues pertaining to contracting and liability, NMFS and PSMFC announced that the JPA could not be established as originally envisioned. For these reasons, the Council voted to cease work on the JPA agreement and extend the current Observer Program structure through the year 2000. During this time, NMFS and Council staff will continue to reexamine the fee-based funding mechanism which was first developed under the Research Plan, as well as examine both short- and long-term adjustments to the existing Observer Program. Discussion of the future structure of the Observer Program is planned for the October 1998 Council meeting.

The Observer Program has developed a computer software application (ATLAS) which allows groundfish observers to enter and send data directly from their assigned vessels and plants to the NMFS office in Seattle. Electronic reporting of observer sampling data from sea using ATLAS is now occurring on about 63 at-sea processing vessels, 11 shoreside plants, and 6 shoreside delivery vessels.

Observer Program staff have been preparing for further expansion of the Community Development Quota (CDQ) program. The CDQ program began in 1992 with the walleye pollock CDQ fishery. It was developed for the purpose of allocating fishery resources to eligible Western Alaska communities to provide the means for starting or supporting commercial fishery activities that would result in ongoing, regionally based, commercial fishery or related businesses. The fixed gear halibut and sablefish fisheries were added to the CDQ program in 1995, and now have been further expanded to include other groundfish species and crab fisheries. In 1999, a multi-species CDQ (MSCDQ) program will combine the existing pollock, halibut, and sablefish CDQ programs with the groundfish and crab CDQ programs. NMFS will be responsible for monitoring and enforcing the groundfish (including pollock and sablefish) and halibut CDQs, and the State of Alaska will be responsible for monitoring and enforcing the crab CDQs.

MSCDQ catch accounting for catcher/processor vessels will be based entirely on data collected by observers. Unlike the open access fisheries where observer data is used to manage a fleet-wide quota, industry participants in the MSCDQ fisheries will require individual accounting of fish harvested in each haul or set. This change in expectations placed on observers, their data, and the Observer Program in general has required much effort by Observer Program staff in the development of special selection criteria and training requirements for MSCDQ observers, development of new sampling strategies and regulations to enhance the observer’s working environment, and changes to the data collection and data management software systems. These changes have already begun and will be further implemented over the next several months.

By Bob Maier.

Resource Ecology & Fisheries Management

Resource Ecology &
Fisheries Management