2/3/11  The National Coalition for Marine Conservation is urging the National Marine Fisheries Service (NMFS) to strengthen a weak proposal to reduce bycatch of bluefin tuna by adding strict limits on bycatch in the Gulf of Mexico, including a closure of the longline fishery during peak spawning season.

The number of adult bluefin in the western Atlantic is about half the number in 1980, when the International Commission for the Conservation of Atlantic Tunas began “managing” the species, and only a quarter of the number of fish around in 1970. The number of breeding-age tuna has actually declined since 1998, when a new ICCAT “rebuilding program” was adopted.

The Gulf of Mexico is the western stock’s only known spawning ground. The fish spawned there in 2003, the largest year class in 25 years of relatively poor productivity, are approaching sexual maturity, when they will return to the gulf to contribute to rebuilding. The need to protect spawning bluefin has never been clearer or more urgent.

On January 13th the National Marine Fisheries Service (NMFS) issued a Proposed Rule to reduce bluefin tuna bycatch in the Gulf of Mexico, but it’s not the answer.

The Proposal

Although fishing for bluefin in the gulf is illegal, longline vessels targeting yellowfin tuna and swordfish catch bluefin incidentally. Hundreds of fish are killed each year on their breeding grounds. NMFS proposes changes in fishing gear it claims could cut the number by more than half (56.5%).

The rule would require longliners to use so-called “weak hooks,” standard circle hooks made of a thinner gauge. Experiments begun in 2007, in cooperation with the longline industry, show some promise of lowering bycatch since the giant tunas (typically over 500 pounds) can straighten the hooks and escape. Unfortunately, weak hooks alone are not the answer, for several reasons:

• The research results are preliminary, based on too small a sample size, and therefore unreliable.

• The effectiveness of the hooks is influenced by how the vessel sets and retrieves the 40-plus mile longlines, which can vary greatly throughout the fleet.

• The rule does not require observers aboard longline vessels to enforce the use of the hooks.

• Experiments so far indicate a potential increase in bycatch of white marlin, another severely overfished species, of 52.7%, which further calls into question the reliability of the study.

Strict Bycatch Limits Needed

The NCMC commends NMFS for recognizing and acting on the need to reduce bycatch of bluefin in the Gulf of Mexico, and for acknowledging that doing so could have “both short- and long-term beneficial impacts on the stock status of Atlantic bluefin tuna”. But the situation is dire enough that we need action now that will guarantee as few spawning bluefin as possible are killed.

Tell NMFS to pull the weak hook rule and replace it with a new one that adds a strict cap on total allowable bycatch in the gulf (as recommended by the Highly Migratory Species Advisory Panel) and a complete closure to longlining during peak spawning season (April-June).

This combination of measures would provide maximum protection for breeding bluefin while providing an incentive for longliners to modify their gear (e.g., weak hooks) or switch to more selective alternatives (e.g., green sticks for yellowfin tuna, buoy gear for swordfish) and keep fishing.