Posted on November, 11 2011

Fishing is a way of life for our coastal communities around the Pacific. We depend on the sea for our livelihood. It’s also an integral part of our culture and traditions. Fishing gear and techniques have continued to develop over the years, some more sophisticated than others, but all are intended to improve or increase catches. The offshore or pelagic (open sea) fisheries are no exception, specifically the longline fishing industry. In order to reduce the capture of non-target species when fishing for tuna, fishing industries are investing in methods that address the issue while maintaining the quota for target species. WWF is working closely with partners to advocate the use of circle hooks to reduce bycatch especially for marine turtles without affecting target catch like tuna and billfish. This type of hook is sharply curved back in a circular shape with the barbed end lying perpendicular to the shank. This article will discuss the major issues arising from offshore fishing including; pelagic longline fisheries, bycatch (non-target species/juveniles of target species) and the introduction of circle hooks.

Presently there is an increase in different fishing methods employed by fisheries that are targeting tuna: many have been modified for the sole purpose of catching certain species of tuna. In the western and central Pacific region there are four commercially valuable tuna species namely; bigeye (Thunnus obesus), yellowfin (Thunnus albacares), albacore (Thunnus alalunga) and skipjack (Katsuwonus pelamis). Pelagic longline fishing employs a main line that is laid out in the sea suspended by a series of buoys and can extend up to 75 kilometres or more. Hanging from this main line are numerous short branch lines at equal
intervals with baited hooks. Hooks that are traditionally used in longline fishing are the Japanese style tuna hooks or J hooks and the Terashima hooks that have been modified and used for decades by fisherman all around the world.

In the Pacific Islands region, incidental catches from longline fishing is a very serious issue. Incidental catch or bycatch refers to marine species that are caught by fisheries which are not the intended or targeted tuna species. For instance, longline fishing for albacore and skipjack tuna can end up catching species such as turtles, sharks, dolphins, whales, seabirds, and juvenile tuna. Because of this, bycatch has become an urgent issue for marine conservation and fishery sustainability. The unsustainable capture of these
vulnerable and threatened marine species continue to be a concern to fisheries scientists, the fishing industry and conservationists alike, so much so that a series of conservation management measures (CMMs) have been developed by the Western and Central Pacific Fisheries Commission (WCPFC or the Tuna Commission) to address this challenge.

When CMMs are endorsed and adopted at the Tuna Commission level its members, which include the Pacific Island countries, are expected to implement these measures at the national level. The CMM on bycatch for example requires the implementation of FAO guidelines to reduce marine turtle mortality in longline fisheries with all vessels carrying turtle de-hookers to release turtles that are captured accidentally.

For sharks the measure allows for the release of live sharks incidentally caught. In addressing the shark fin issue the measure ensures that shark fins on board a fishing vessels must total no more than 5% of the weight of shark carcass on the vessels. This will discourage unscrupulous fishing operators from only taking shark fins and tossing the dead carcass back into the ocean. In other oceans, management measures such as shark fins still attached to the dead shark is mandatory for all fishing vessels. A number of bycatch species are listed as endangered or threatened on the IUCN Red List of Threatened Species.

The results of previous studies conducted around the world have been very promising. It has been proven that the use of circle hooks reduces marine turtle bycatch on longlines fisheries without affecting the rate of tuna catch. Circular hooks are less likely to be swallowed by turtles than the traditional J-shaped hooks. The US National Oceanic Atmospheric Administration (NOAA) and MUSTAD, the world’s leading fishing hook
producer based in Norway have donated over 250,000 circle hooks to WWF for trials in the East and West Pacific Ocean. Unfortunately the traditional J-hooks still remain a popular choice for longline operators.

A new report released by WWF and the Inter-American Tropical Tuna Commission (IATTC) on alternative fishing technology outlines the transition from J-hooks to circular hooks, identifying training needs and tools required to release turtles captured accidentally. Independent observers on board the fishing vessels collected data that showed an overall reduction in bycatch for marine turtles and sharks.

The opportunity currently exists for the uptake of circle hooks by fishing companies and to start moving towards sustainably caught seafood products. Major seafood retailers in the European Union and North America are now seeking to source sustainable and responsibly caught seafood including tuna. Fishing and bycatch best practices are what “green” fish buyers and retailers are now looking for. There is currently a growing awareness and desire for sustainably caught tuna. This growing international demand will influence where they will source and who they will buy their tuna from.