Bluefin Tuna And The Trouble With Fish Farms

By Julie Rooney

Posted August 1, 2011

Bluefin tuna is a favorite among sushi and seafood lovers for its flavor and melt-in-your-mouth texture. However, without changes to the way humans harvest this famous fish it may disappear from the oceans forever.

Bluefin Tuna Face Extinction

Because of overfishing and pollution, the Southern bluefin tuna was recently classified as a critically endangered species.

The World Conservation Union (IUCN) says that without global protection tuna will go extinct. They specifically point to high market prices because of popular demand as a main motivator of overfishing. Europe has already exceeded the amount of fish it can sustainably catch for 2011.

"All three bluefin tuna species are susceptible to collapse under continued excessive fishing pressure. The Southern bluefin has already essentially crashed, with little hope of recovery," says Kent Carpenter, the IUCN's Marine Biodiversity manager.

The Trouble With Fish Farms

Unlike salmon, tuna are almost impossible to farm. Tuna have long lives and do not reach sexual maturity until they are five to six years old. Born in Pacific waters around Japan, tuna swim to Mexico when they are one to two years old and remain there until they return to Japan to breed.

This means that any farmed tuna must be wild caught at some point. Fish farms that are increasingly emerging off of Mexico's coast capture the young fish and feed them so that they yield more flesh when slaughtered. However, these fish never return to Japan to breed and so the wild population becomes lower.

The fish farms say that capturing the tuna to fatten up before slaughter is more environmentally sound because it means that less fish will need to be caught to meet the same consumer demand. Fatter fish give more meat so fewer individual fish are needed.

Only the Kinki University in Japan has been able to successfully breed, raise and slaughter tuna in a closed loop cycle, which raises hope that tuna farms can rely independently of wild-caught tuna in the future.

More U.S. Fish Farms

98 percent of the 5 billion pounds of seafood that Americans consume annually are imported. Because of this, the National Oceanic and Atmospheric Administration (NOAA) and the Commerce Department have opened offshore federal waters to fish and shellfish farms.

They hope this will boost American seafood production, create new jobs, provide safer seafood, and help to regulate environmental protections on fish population. A spokeswoman for the NOAA says that all new fish farms must obey federal regulations that seek to protect wild species and ocean ecosystems.

Seafood operations supported by this push for domestically raised fish and shellfish can exist inland as well as on the coast.

Environmental Health Vs. Profits

However, environmentalists says that fish farms will come at a price to ecosystems.

Fish farms rely on wild caught feeder fish like sardines that will reduce the amount of food for wild fish. Disease can spread from fish farms to wild populations and animals like sharks, whales, and dolphins can be caught in fish farm nets. Like other factory farms, the use of antibiotics can spread through the environment to sealife and make antibiotic resistant bacteria.

Environmentalists also worry that big companies and agribusiness interests will lobby against environmental protection in the interest of creating higher revenues. They point to the decade old fish farming industry in Hawai'i that is reliant on taxpayer money, has employee violations, and harms Hawai'i's natural habitat.