If you've been to the supermarket lately, you've probably seen tuna for sale in cans and pouches, and perhaps even in the fresh or frozen fish section. What you probably have not seen is information about where this tuna comes from. Yes, you might see that much of it is dolphin-safe, and that's a step in the right direction, but there is more to be done if we are to help tuna - and the ocean's ecosystem - thrive.
Tuna in Peril
There are eight tuna species, and some are far from endangered, meaning not all tuna products are poor food choices. If you like to eat tuna, you do want to limit your intake since this slow-growing fish can contain high levels of mercury, which can be detrimental to your health. Be sure to look for the Marine Stewardship Council seal of approval before purchasing tuna. This being said, you won't find that seal on most tuna products - therein, lies the problem; many tuna products contain endangered Bluefin Tuna.
These fish traditionally inhabit waters from Iceland to the Canary Islands, along with waters along the east coast of Canada, plus Newfoundland, the Gulf of Mexico, and the Mediterranean Sea. Capable of diving to depths of 3,280 feet, they grow to be as long as 21 feet, and can weigh in at as much as 1,600 pounds, though the average Bluefin is 6 to 7 feet long and average weight is 600 pounds. Why is this important? The size of the average Bluefin has dropped by 50% since the 1970's, when the fish weighed in at an average of 1,200 pounds apiece.
While Bluefins can live to be as old as about 30 years, few survive to old age today. Their natural predators are sharks and killer whales; now, man has joined the list and caused decimation via overfishing. Since the 1900's, when factory fishing was first introduced, Bluefin Tuna numbers have declined markedly; in the Mediterranean, 97% of Bluefin stock has been depleted, and throughout the fish's range, 90% of stock has been depleted. Despite this decline, a 2010 measure proposing a worldwide ban on Bluefin tuna fishing was rejected.
More alarming, more than half the worldwide fleets hunting Bluefin Tuna are operating in the Mediterranean. Nations currently fishing for Bluefin include:
- Australia
- Cape Verde
- Croatia
- Cypress
- Greece
- Italy
- Indonesia
- Japan
- Libya
- Malta
- Mexico
- Oman
- Panama
- Philippines
- Portugal
- Spain
- Tunisia
- Turkey
Of these, Australia and Japan operate the largest fisheries, with most consumers being located in Japan. As of late 2012, Bluefin Tuna fisheries were a $7.2 Billion industry worldwide, with most Bluefin being consumed as steaks, sushi, and sashimi. If you want to avoid it, along with the elevated levels of mercury and PCBs it contains, watch out for sushi and sashimi labeled as Hon Maguro or Toro (Tuna Belly).
The Bluefin's Environmental Role and Implications of Overfishing
Bluefin Tuna are important predators, consuming a diet consisting primarily of herring, hake, mackerel, menhaden, crustaceans, and squid. In addition, they are a crucial prey animal for apex predators. As you may be aware, when apex predators suffer, entire ecosystems are at risk of collapse. In addition, unsustainable methods including purse-seining are being used to capture these tuna, and some are being transferred to fish farms, where they are fattened up prior to being killed. Farmed tuna do not help the environment, and in many cases, tuna farms increase pollution.
In addition to reported and legally caught catches, Bluefin are subject to illegal fishing and juveniles are often caught without proper reporting. As a result, the Bluefin population is in danger of complete collapse.
We, as consumers, play an important role in helping Bluefin Tuna survive. First, it is vital that we educate our families and friends about the importance of choosing only MSC certified fish for consumption - not just for species preservation, but for our own health. Second, we can make our voices heard by alerting elected representatives and heads of state about the problem. Finally, you can support organizations like Sea Shepherd, Ocean Champions, Greenpeace, and others who make it their mission to raise awareness and to prevent overfishing from occurring. These are efforts all who care for the oceans should support. After all, we all rely on healthy oceans to survive.