Wednesday, November 18, 2009

Losing the Conservation Battle With Atlantic Bluefin Tuna

Issues that affect us in New Jersey, sometimes have much larger repercussions in our Northeast region, nationally or even internationally.

Many fisheries issues fall into that latter category.

Some environmental groups, such as Greenpeace, are saying that at the annual International Convention on the Conservation of Atlantic Tuna (ICCAT) delegates are ignoring the advice of their own scientists and will continue fishing the endangered bluefin.

As reported in The Times (UK), the convention’s department of research announced last month that the stock was depleted enough to justify banning international trade. A moratorium on catching bluefin tuna is widely regarded as essential for the survival of the species, but the EU is discussing the highest possible quotas. This EU delegation is reportedly comprised mostly of representatives from the fishing industry.

Once again, politics and the environment mix.


Bluefin tuna from the eastern Atlantic spawn in the Mediterranean. It is an ancient industry, going back 9,000-years.

But 72% of the species numbers are gone after 40 years of, what some call, "mismanagement."

There are a number of tuna species and all are heavily fished globally. The type you are most likely to eat comes in a can. Canned tuna fish used for sandwiches and salads comes from either skipjack (“light meat tuna”) or albacore (“white meat tuna”). Both are small tuna species.

The larger yellowfin and the bigeye tuna are larger species that are usually served grilled.

The bluefin tuna is a giant and the first choice for sushi and sashimi, making it perhaps the most desirable food fish in the world. With that demand, comes a high monetary return and the threat of overfishing.

Scientists list the bluefin as probably the most endangered of all large fish species and it is approaching extinction.

Currently, fish farmers have not been able to to breed the tuna in captivity to any marketable degree.

Bluefin was not always so popular. Early in the last century, it was nicknamed the “horse mackerel.” Its red, strong-flavored flesh was not considered suitable for humans and was used as dog and cat food. Off the NJ coast, it was popular mostly as a big-game sport fish.

Bluefin tuna Fish Facts
  • maximum known weight close to three quarters of a ton
  • maximum length of four meters
  • Unlike most fish species which are cold-blooded, the bluefin is one of the few warm-blooded fishes. They can maintain a body temperature of 27 degrees C (81 degrees F for American readers), which is pretty close to that of a mammal. 
  • among the fastest of all fishes - capable of speeds up to 80 kilometers per hour
  • able to migrate across entire oceans, taking advantage of its tapered, bullet-shaped body and rigid, quarter-moon tail
  • bluefins often hunt in packs. They hunt by vision.
  • their diet is varied - a stomach-contents study found mackerel, bottom-dwelling flounder, sedentary sponges, Atlantic herring, sand lance, bluefish, squid, butterfish, silver hake, windowpane flounder, winter flounder, menhaden, sea horses, cod, plaice, pollack, filefish, halfbeak, sculpin, spiny dogfish, skate, octopus, shrimp, lobster, and crab - almost anything that swims, floats, crawls or lays on the bottom.


Even with lower quotas on Bluefin fishing, the species will still be endangered.

This is especially true because the global tuna fishery is so badly regulated and enforced. There are many reports of fleets that ignore quotas, restrictions, boundaries, and any other regulations.

The market in Japan is the biggest problem. 60,000 tons of bluefin a year - more than 75% of the global catch - goes to Japan where fleets circumvent even their own country’s restrictions.

Ironically, as the tuna populations continue to fall, demand increases and prices increase, which means increased incentive to intensify fishing.

The Japanese giving up their consumption of maguro (tuna sushi) has been compared to Americans giving up hamburgers.

Though lower quotas need to be set and enforced, other types of rescue and fish-farm breeding may be necessary to save the species.

Bluefin tuna in Peril - Scientific American
"EU set to ignore advice to ban bluefin fishing says Greenpeace"   Times (UK)

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