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Describing the Vertical Habitat of Bigeye and Albacore Tunas and Post Release Survival for Marlins in the Central Pacific Longline Fisheries with Pop-up Archival Transmitting Tags


Progress Reports (PDF): FY 2010, FY 2009, FY 2008, FY 2007, FY 2006, FY 2005, FY 2004

Project Overview
Project investigators plan to attach pop-up archival transmitting tags (PATs) to large pelagic fish captured by longline fishing gear in the Hawaii and American Samoa fisheries. These tags will be used collect a long term record of the animal's position, depth and water temperature. After a predetermined time interval the tags will detach and transmit these data to researchers via the ARGOS satellite. Three species will have the highest priority for tagging - bigeye tunas and marlins in the Hawaii fishery, and albacore in the American Samoa fishery.

Bigeye tuna is the target species in the Hawaii tuna longline fishery and albacore is the target species in the American Samoa longline fishery. For both these species there is a need to gain information on their vertical habitat and migration, data that can be obtained through the use of PAT tags. For marlins, the issue of releasing these fish caught in longline gear is a growing management issue. Information on the survival of marlin released after capture needs to be collected to address the potential effectiveness of management requiring release of marlins. PAT tags are ideally suited to address capture and release mortality. PAT tags have a depth release mechanism that will release at 1500 m if the fish dies and sinks and the subsequent time/depth profile clearly identifies this as a mortality rather than a tag shedding event.

The objectives by priority are to use PAT tags to:

  1. determine the vertical habitat of bigeye tunas in the Hawaii fishery and albacore tunas in the American Samoa fishery to improve stock assessments;
  2. estimate the post release survival of striped and blue marlins in the Hawaii longline fishery;
  3. determine the temperature and depth distribution data to estimate the vulnerability of marlins to fishing gear set in deep and shallow configurations;
  4. estimate the horizontal movement data for bigeye and albacore tunas and marlins to address the spatial scale appropriate to the management of fisheries of each species;
  5. obtain information on the oceanic habitat used by deep-diving species for the pelagic ecosystem including opah, ono, mako and thresher sharks.

Year 1 funding for this 3-year project to be available early 2003.

 

Principal Investigators:
Dr. Jeffrey Polovina
National Marine Fisheries Service
Honolulu Laboratory
2570 Dole Street, Room 216
Honolulu, Hawaii 96822 USA
Phone (808) 983-5390
FAX (808) 983-2902
email:Jeffrey.Polovina@noaa.gov


Michael Seki
National Marine Fisheries Service
Honolulu Laboratory
2570 Dole Street
Honolulu, Hawaii 96822 USA
Phone (808) 983-5393
FAX (808) 983-2902
email: Michael.Seki@noaa.gov

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This page updated September 29, 2010