America’s Favorite Fish Tainted by Porpoise Deaths

Next time you order a tuna salad or sandwich, consider this: In order to catch one of the most popular tuna varieties, the world’s fishing fleets each year kill more than 125,000 porpoises--the marine mammals counted among the world’s most gentle and intelligent creatures.

Last week several environmental groups launched a boycott of canned tuna and filed a federal lawsuit in San Francisco, accusing the Department of Commerce and its National Marine Fisheries Service of failing to enforce laws that protect porpoises.

Four years ago Congress banned tuna imports from nations whose rate of porpoise kills exceed that of the U.S. fleet, but it took the National Marine Fisheries Service until last month to come up with pertinent regulations, effective April 18. Henceforth if foreign countries want to sell tuna in the United States, they will have to meet the same porpoise mortality rates as the U.S. fleet, and must supply data from observers to prove it. But the rules provide a long period--until 1991--before foreign nations absolutely must comply. “Depending on whether or not a foreign country is willing to share its mortality data with us, we could embargo their tuna by next year, or as late as 1991,” said Brian Gorman, a Commerce Department spokesman.

The Marine Mammal Protection Act, passed in 1972, stated that porpoise deaths from tuna fishing should be “a number approaching zero.” The U.S. tuna industry won a provision in 1981, however, that allows the 35 boats in the American fleet to kill up to 22,500 porpoises each year.

The playful cetaceans are killed in the hunt for just one tuna species--yellowfin, the most common kind on market shelves. The issue extends as far back as the 1940s, when tuna fishing began in the United States and bait boats first sailed out from San Diego and San Pedro. In the beginning, tuna fishermen quickly discovered a phenomenon that to this day baffles the experts: In the southeastern tropical Pacific, yellowfin tuna follow certain types of porpoise.

By locating schools of porpoise, fishermen also found the tuna. Once the bait boats got close to the porpoise, fishermen hurled thousands of live bait fish into the sea to start the tuna in a feeding frenzy.

During those early days, fishermen and porpoise were allies; by using their sonar capabilities, porpoise could detect the metal hooks and bit only live bait, while the tuna bit voraciously at anything shiny, even the naked hooks that the fishermen adeptly yanked from the water, hurling the tuna over their heads and into bins. Old-time fishermen say porpoises would actually come to them instead of their having to seek out the porpoises.

Everything changed in the 1960s with such technological developments as nylon netting and ammonia-cooled refrigeration systems--both of which are now used by tuna seiners to capture and preserve tuna. As a result, bait boats became obsolete and tuna seiners capable of holding more than 1,700 tons of fish began leaving shipyards for the open sea, where they destroyed the once fragile coexistence between commerce and marine-mammal ecology.

Engaging in a kind of salt-water rodeo, tuna seiners, along with thespeedboats they carry on board, herd schools of porpoise together, making them tight enough for a mile-long net to be “let go,” encircling both porpoise and the associating tuna.

Porpoise cannot swim backward; when they come into contact with netting, they can only move straight ahead, to become helplessly entangled in the net underwater, preventing them from rising to the surface to breathe. Each year thousands of porpoise suffocate in tuna nets in spite of the often-valiant efforts of fishermen to release them unharmed.

During the early years of tuna seining, fishermen returned from sea telling horror stories of how entire schools of as many as 10,000 nettedporpoises were slaughtered at a time. In 1972 public outcry resulted in the passage of the Marine Mammal Protection Act. The U.S. tuna fleet, then the largest in the world, was required to abide by strict governmental regulations. Among other things, the act requires observers aboard all U.S. seiners to count the number of porpoises killed and to provide verification for a quota system. If the American fleet reached a certain level of kill--now set at 20,500--no further fishing for tuna that attract porpoises is allowed for that year.

Because of high U.S. labor costs, foreign firms have taken away much of the tuna business from the United States; American boats today catch only about 16% of tuna destined for cans. Countries such as Mexico now dominate the industry and consequently do most of the killing of porpoise. Mexico does not recognize the Marine Mammal Protection Act; after the Reagan Administration lifted an embargo against Mexican tuna in 1986, Mexico was able to compete in the U.S. marketplace while slaughtering porpoises with impunity. As a result, a number of Pacific porpoise species are in danger of extinction.

While groups like Earth Island Institute, headed by David Brower, call for a total boycott of canned tuna, a boycott of yellowfin would be more to the point. The problem is that in most cases, consumers can’t tell what’s in the can. There are several kinds of tuna--albacore, big eye, bluefin, skipjack--that do not associate with porpoises, and catching them does not endanger porpoises. In supermarkets today, the only easily recognized cans of tuna harvested from fish caught without endangering porpoises are labeled albacore , or “white meat tuna.” Other types are not specified, and can be sold separately or mixed with yellowfin.

The phenomenon of yellowfin tuna associating with porpoises exists only in the southeastern, tropical Pacific Ocean. There are other effective commercialmethods of catching yellowfin without killing a single porpoise. The U.S. fleet employed two such methods in 1986 after reaching their porpoise-kill quota of 20,500. The result was ironic: Catching “school fish”--free-swimming tuna not involving porpoise--and “log fish”--localized tuna associated with floating objects--U.S. fishermen actually caught more tuna in two months than any comparable period that year.

With the ability to distinguish canned tuna labeled albacore, the consumer has a choice, although limited. Unfortunately, albacore is the most expensive tuna; advising consumers to eat only albacore would be a “let-them-eat-cake” solution. A better answer might be a campaign to demand national legislation requiring easy-to-recognize emblems on cans of tuna not produced from fish that attract porpoises. Concerned shoppers could then enjoy both tuna and peace of mind by knowing their meal was not provided at the expense of the endangered cetaceans.

U.S. tuna fishermen have pioneered and refined some of the most effective techniques to reduce the death of porpoises, though the methods are still woefully inadequate. The major share of blame for the mass killing of porpoises rests with those who profit most: canners. Instead of encouraging alternative methods that don’t endanger porpoises, canneries seek yellowfin tuna because the fish are large and consequently cost-effective for processing.

If the canneries were required to be accountable, they would find practical solutions to a problem they have helped create and from which they richly profit.