Expired · 30th November 2010
The fish really is magnificent. The blue-black of its back slowly rainbows to aquamarine and whitish green on its sides and then to the pure wet silver of its belly. The rotund torpedo shape, the unique dorsal markings and the scimitar curve of the tail identifies this fish as a bluefin tuna, one of the most powerful swimming machines on the planet.
But this particular fish hangs vertically from a metal hook on a Nova Scotia wharf, its mouth agape and Its large dark eyes staring blankly at the high-tech rubber boots of the man who took four hours to boat it. Even in silent death the tuna still possesses a regal dignity. Not even the affront of the heavy rope suspending it by the tail can rob this 240 kilogram fish of its marine nobility.
Drew Voegli, a tanned and fit-looking young man with curly hair and stylish sunglasses, seems small as he stands in profile beside his trophy. It is at least three times his girth, and taller than him by half. His hand rests gently on the side of the fish, a respectful touch that contrasts with the hours of brutal contest between the test of his mastery and the tuna's ancient will to swim freely in the ocean of its origin.
This contest between man and fish, once so heroic and venerable, now has a different symbolism. The Nova Scotia International Tuna Tournament, offering one of the oldest sporting trophies in the world, is targeting a fish that is at the edge of commercial extinction. The bluefin tuna, the most coveted of all catches, has been exploited by the industrial fishery to the limits of its survival as a species. Within a decade, at present harvest rates, it will exist only as a rarity, hurried even faster to species oblivion because one of its two breeding areas in the Mediterranean and Gulf of Mexico has been massively poisoned by BP's Deepwater Horizon oil well blowout.
But the plight of the bluefin tuna marks more than its own demise. Industrial fishing of the world's oceans is depleting almost all stocks at an alarming rate. When sustainability is plotted against catch from 1950 to 2010, the graph shows a steepening arc plunging downward at 60 degrees from the late '50s (New Scientist, Mar. 7/09). If our present oceanic fishing practices are not radically reformed, no more commercial wild fish stocks will remain after 2040.
This extremely serious situation is highlighted in an article by Caroline Williams, The Next Big Fin (Ibid.). The editor introduces her article with a stinging facetiousness. "With many seafood species exploited beyond their ability to bounce back, it's time to look for tasty alternatives. Anyone for squid, algae or jellyfish?" And Williams adds in her article, "How about some squid and chips? Perhaps an algae burger" with some "crunchy fried jellyfish rings on the side?"
The playfulness is deadly serious, with huge implications for ocean ecology and the nutritional well-being of humanity – we get 20% of our animal protein from the oceans. Williams notes that "75% of the world's fish stocks are either fully exploited, over-exploited or recovering from past depletion." Increasing demand for fish because of rising population and affluence collides with dwindling stocks means that more and more effort and technology are required to maintain existing levels of catch.
Accordingly, the fishing industry has now "shifted its focus down the food chain." With stocks of tuna, marlin, cod, haddock, hake, plaice and other species depleted, attention has moved to feed-fish such as sardines and anchovies. But depleting either the big fish or the little ones tips the marine ecology out of balance in favour of squid, jellyfish and algae. "Blooms of jellyfish" have appeared off the coast of Namibia and Alaska, in the Black Sea, Mediterranean, Gulf of Mexico and the Sea of Japan. When Namibian annual fish catches plummeted from 17 to 1 million tonnes, jellyfish soared to "12.2 million tonnes, more than three times that of mackerel, hake, sardines and anchovies combined" (Ibid.). Jellyfish in 2003 were so dense in the Sea of Japan that they were "clogging and bursting nets, causing high mortality of the catch due to venom, increasing the risk of capsizing trawlers and giving fishermen painful stings."
The option to harvesting wild food from the ocean is aquaculture, now the source of more than half our seafood. But farming salmon, a carnivorous species, presents profound ecological problems. When 6 tonnes of wild feed-fish are needed to produce 1 tonne of fish meal, and when 1.5 to 3 tonnes of fish meal are needed to produce 1 tonne of farmed salmon, this means that 1 tonne of farmed salmon could cost the ocean's ecology up to 18 tonnes of critically important fish resources (New Scientist, Apr. 3/10). With global production of farmed salmon at about 1.4 million tonnes per year, then the impact on the ocean's biological balance is foreboding.
The biological mechanisms are clear. Catch too many big fish and the squid population explodes. Catch too many little fish and the jellyfish population explodes – without the little feed-fish to eat jellyfish larvae, the unchecked jellyfish feast on zooplankton, and without the zooplankton to eat the phytoplankton (algae), the phytoplankton explodes, which then dies, rots and causes anoxic dead zones.
Any government with an iota of awareness knows where this is leading. If we can't eat our traditional ocean fish because there aren't any, we could eat squid or feed-fish. If we can't eat squid or feed-fish because there aren't any, we could eat jellyfish and phytoplankton – jellyfish are not very nutritious and, even after long processing, they apparently taste like "slightly tough strips of cucumber". As for the phytoplankton – which apparently tastes like cheese – we would have to strain the ocean for its unpredictable blooms and separate the edible varieties from the toxic ones, presently a commercially impossible task.
Perhaps the blank gaze of the magnificent tuna hanging from the wharf in Nova Scotia is staring into our future if governments don't curtail industrial fishing and designate one-third of our oceans as "no-take" zones. The alternative will be squid, jellyfish or algae.