The Most Remote Fishery on Earth
SOUTHERN OCEAN– Antarctic fish are a strange and fascinating breed, drawing scientists from all over the world to study their unique polar adaptations. Many Antarctic fish have proteins in their blood that possess antifreeze properties, allowing them to survive in the freezing waters of the Southern Ocean. Species in the Icefish family lack hemoglobin, a strange adaptation that gives them clear blood, lending to their family name. And many fish lack swim bladders, instead controlling buoyancy through lipids (or fats) and weakly calcified skeletons. Few people would have seen the potential for harvesting these bizarre fish.
In the late 1960s fisherman began trawling around the sub-Antarctica islands, mostly for Notothenia rossi (the marbled rock cod) and some species of Icefish. Catches rose steadily, and by 1990, the marbled rock cod population was reduced to 5% of its pre-exploitation level. As shallow water species became depleted, fishermen began targeting the large deep-water Patagonian toothfish, finding a temporary goldmine. But legal commercial fishermen weren’t the only ones interested; pirate fishermen also wanted their share. Within ten years local population declines and stock closures ensued. Consequently, fishing boats pushed into the southernmost reaches of the Antarctic waters in pursuit of the Patagonian toothfish’s cousin species, the Antarctic toothfish. Toothfish are more commonly known by their snazzy market name “Chilean Seabass.” And they are an incredibly expensive and gourmet fish – prices are well over $20 per pound – which is the main reason why the fishery plunders on, despite stock depletions and the potential vulnerability of these fish.
Why would people go all the way to Antarctica to fish? Indeed, it makes little sense to use so much gas, time and energy traveling to the most remote corner of the globe in pursuit of fish. But our fisheries closest to home have been highly exploited and can no longer meet the needs of a growing world population. Current Food and Agricultural Organization (FAO) statistics regarding world fisheries show that 38% are fully exploited, 28% are overfished, and 29% are collapsed. That leaves only 3% of our world fisheries unexplored, including some stocks of Antarctic toothfish. Fishermen are forced to voyage into deeper and more remote waters to keep up with world demands and continue fishing, with or without a license to do so.
The problem with deep-sea fisheries
Last year I attended a symposium on deep-sea fisheries at the AAAS meeting in San Francisco. I listened in earnest, scribbling down notes as all the fishery biologists on the panel – including world renowned fishery experts like Daniel Pauly – stood up and talked about the vulnerability of deep-sea fisheries. Deepwater fish tend to grow slowly, live a long time, mature later in life and have low fecundity (reproductive capability.) The symposium led to a clear conclusion: deep-sea fisheries are not resilient to heavy commercial exploitation. In the past we realized this too late, after the deepwater fishes had been over-harvested.
Toothfish fall into the category of relatively slow-growing and long-lived fish — 50 years for the Patagonian species and about 40 for the Antarctic species. They don’t mature until about 10 years of age and are caught well before that time, one of the reasons we have yet to understand their reproduction and fecundity. While the Patagonian toothfish has already been overexploited in some areas, the fishery for Antarctic toothfish is still relatively new, though it is growing and will continue to do so. Given the trends of Antarctic and deep-sea fisheries, the chances that toothfish could withstand heavy fishing pressure seem slight. Toothfish are the largest fish in the southern ocean, and decimating their population could be damaging to the whole Antarctic ecosystem.
Will we learn from the past quickly enough to keep the Antarctic toothfish from becoming another over-fished FAO statistic? My job as a fisheries biologist is to provide life history information on the species. The managers’ job is to use that information to implement sustainable management. And your job as a consumer is to make the best choices about where the fish you eat come from. Being out here in the Southern Ocean, the question I can’t shake from my mind is: Do we really have any business commercially harvesting fish that come all the way from Antarctica?
For more on Antarctic fish, check out the BBC’s recent article on the Antarctic toothfish by clicking here.