PIFSC Stock Assessment Scientists Participate in 10th ISC Plenary

Scientists of ISC member countries work together to provide information on the biology and stock 
            status of tunas and billfishes in the North Pacific, including (top to bottom) albacore, swordfish, and 
            striped marlin.
Scientists of ISC member countries work together to provide information on the biology and stock status of tunas and billfishes in the North Pacific, including (top to bottom) albacore, swordfish, and striped marlin.

The 10th Plenary of the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC) was held in Victoria, B.C., Canada from 21-26 July 2010. The meeting was attended by delegations from ISC members Canada, Chinese Taipei, Japan, Korea, Mexico, and the United States, and representative of the North Pacific Marine Science Organization. The U.S. delegation, led by acting Southwest Fisheries Science Center (SWFSC) Director Usha Varanasi, included significant participation from PIFSC stock assessment scientists. In addition to the usual business of the Plenary, a special seminar was convened on oceanography and low trophic-level habitat in the North Pacific.

The ISC10 Plenary reviewed reports of the ISC working groups for billfish, Pacific bluefin tuna, and other species. Based on these reviews, the Plenary concluded that:

  • The eastern Pacific stock of swordfish is healthy and in good condition.
  • The fishing mortality rate for Pacific bluefin tuna, particularly on juveniles, needs to be decreased.
  • Conservation recommendations for albacore, striped marlin and the western and central North Pacific stock of swordfish made at ISC9 should be maintained with minor changes for clarification.

The Plenary endorsed candidate biological reference points for stocks of highly migratory species in the North Pacific developed by the Albacore, Pacific bluefin, and Billfish Working Groups. These were forwarded to the Northern Committee of the Western and Central Pacific Fisheries Commission for consideration at its 6th regular session in September 2010.

The Plenary agreed to dissolve the ISC Bycatch Working Group and create a Shark Working Group. It endorsed the recommendation of the Billfish Working Group to postpone convening a world blue marlin symposium.

The ISC work plan for 2010–2011 includes completing new stock assessments for albacore and striped marlin by the next plenary session (ISC11) to be held July 2011 in the U.S. Other work plan elements include continuing preparations for Pacific bluefin tuna and blue marlin stock assessments in 2012, improving management of the ISC database, improving the ISC website, and updating and clarifying ISC operations procedures.

After five years of service as Chair of ISC, SWFSC scientist Gary Sakagawa stepped down from the position. The Plenary elected Gerard DiNardo, leader of the PIFSC Stock Assessment Program, to serve as ISC Chair during 2010–2013.

The ISC10 Plenary report is available on the ISC website at http://isc.ac.affrc.go.jp/pdf/ISC10pdf/ISC10_Plenary_Final.pdf