link to AFSC home page

link to AFSC home page link to NMFS home page link to NOAA home page

Resource Assessment & Conservation Engineering (RACE) Division

AFSC Quarterly
Research Reports
April-May-June 2007
Contents
Feature
ABL Reports
FMA Reports
NMML Reports
RACE Reports
REFM Reports
Quarterly Index
Quarterly Home

Recruitment Processes Program

Eastern Bering Sea and Gulf of Alaska Cruises

scientists lowered from the deck of the Healy
Scientists and their sampling equipment are lowered from the deck of the USCG icebreaker Healy to the Bering Sea pack ice below.
 

Scientists from the Recruitment Processes Program had a busy spring with involvement in four cruises in the eastern Bering Sea and Gulf of Alaska. The first cruise (10 April - 12 May), a collaboration with the National Science Foundation BEST (Bering Ecosystem Study) and NOAA’s Pacific Marine Environmental Laboratory (PMEL), used the USCG Icebreaker Healy to sample larval fish and zooplankton behind the seasonal ice edge in the eastern Bering Sea.

Other AFSC projects on the icebreaker included researchers from MACE using acoustics to document under ice fish distributions (see previous report) and researchers from the National Marine Mammal Laboratory (NMML) investigating the distribution and ecology of ice-dependent seals (see NMML report in this issue). The general goal of the research is to understand how sea ice affects the structure and function of the Bering Sea ecosystem so that we can predict how the loss of sea ice will affect this region.

This was the Recruitment Processes Program’s first opportunity to use a vessel capable of working well within the ice field, and taking advantage of this opportunity, we collected many plankton samples for later analyses in the laboratory. Scientists also periodically took samples of the ice for its physical, chemical, and biological properties. Recruitment Processes scientists also had the opportunity to talk to students from St. Paul and St. George Islands about the cruise and careers in science during a stop over and crew change at St. Paul Island.

The second cruise (7-18 May) was aboard the NOAA ship Miller Freeman in the Gulf of Alaska. Samples were collected for a project that aims to understand the mechanisms important for the transport of larval flatfish from the continental slope, inshore to nursery areas on the Bering Sea shelf. The North Pacific Research Board helps support this research, and the target fish is Greenland halibut (Reinhardtius hippoglossoides). Samples were collected primarily around the Pribilof Islands and Bering Canyon. Greenland halibut larvae were in some of the plankton tows and were shared with our collaborators from Oregon State University.

Recruitment Processes scientists also conducted our annual walleye pollock late larval cruise in Shelikof Strait, Gulf of Alaska. This cruise was also aboard the Miller Freeman and began in Dutch Harbor and sampled from Unimak Pass up to the middle of Shelikof Strait. The main objective of the cruise is to determine the number of larvae that have survived to the late larval stages and could potentially recruit to the fishery 2 years later. The abundances and size of the larvae are used to help predict potential recruitment of the year class.

Recruitment Processes scientists, as well as others from RACE Division Pathobiology and the AFSC Fisheries Interaction Team, oversaw the collection of ichthyoplankton and zooplankton on the 2007 eastern Bering Sea groundfish survey. These samples were collected to maintain the time series of plankton species and abundance from the Bering Sea ecosystem. These data are invaluable to understand if and how the ecosystem may be changing in response to climate.

By Jeff Napp
 

<<< previous

next >>>


            Home | FOIA | Privacy | USA.gov | Accessibility      doc logo