By 2048, the fish we know today will have disappeared, marine scientist Callum Roberts warns John Daly.
WHEN Callum Roberts speaks at the West Cork Literary Festival next Tuesday about the remarkable story of humanity’s relationship with the sea, he will be assured of an attentive audience given the region’s long maritime history.
Indeed, all of us on this island nation would do well to heed his thoughts on our relationship with this once rich resource, and how over-exploitation is ruthlessly decimating its disappearing bounty.
A marine scientist at the University of York, Roberts is the author of The Unnatural History of the Sea, and Ocean of Life: How Our Seas Are Changing, both of which explore how the seas are changing and how we must alter course at this eleventh hour to avert disaster.
“For most of human history, the seas have pretty much taken care of themselves and we haven’t had to care about how much we took from them,” says Roberts. “Throughout history there was always plenty to be had from them, even with all of the pollution we put into them. But humanity’s numbers on Earth have expanded so rapidly over the past 50 years that we have come to exert a global influence over the oceans to the point that we now have to take care of the impact we are having,” he says.
Roberts outlines a devastating account of the effects of overfishing, where once abundant life has declined to the levels of less than 5% of the total mass of fish that once existed around Europe. While a lack of conservation over the centuries threatened species, it is only in the last half-century that trawling has eliminated entire habitats, including that of cod off Canada, oysters in Chesapeake Bay and herring in the North Sea. With the weight of technology being brought to bear on the oceans, devices such as sonar depth sensors and aerial tracking are being used to plunder the last frontier. At the current rate of destruction, by 2048 most of the fish species we take for granted today will have completely disappeared.
“The intensity of fishing has been ratcheted up throughout the 20th century through constant innovations like monofilament nets and echo sounders back in the 1950s, up to the sophisticated computer electronics prevalent today,” he says. “The emerging threat of extinction is now upon us, in particular iconic species like the bluefin tuna.”
With a single bluefin selling for $100,000, these fish are now so valuable that planes and helicopters are hired to scan the ocean for them. “It isn’t fishing anymore, it’s extermination,” says Roberts.
The insidious creep of global warming is also contributing to this maritime genocide, particularly in the mass migrations of certain species into new territories, a phenomenon that even recreational fishermen in Ireland will have noticed.
“Mackerel shoals are moving further north than they ever did before, for example, outside the borders of the EU and into that of the Faroes and Iceland. This, is turn, prompts new and often difficult political situations as countries argue over who owns the resource. We will see more and more cases like this,” he predicts.
Smaller countries like Ireland, maritime nations who draw upon their prosperity from the surrounding seas, will suffer more than most in this changing cycle, Roberts believes. “Reading governmental reports from the early 19th century shows just how incredibly abundant the seas around Ireland were then, and how sadly different the situation is today. Species like cod, conger and skate, once so plentiful, have suffered from ever more invasive fishing methods from the sail trawlers of the early 1900s up to the diesel factory ships of today.”
Such is the current level of net trawling that the boulders on the sea floor have been polished clean from repeated sweeping by enormous nets. Each night across the globe, nets measuring 500 times the circumference of the entire globe are set in the world’s oceans.
Fish farming has been an unregulated area of activity for too long, says Roberts. “Outbreaks of disease do affect stocks of wild salmon and can produce concentrated areas of pollution in areas of low water circulation.”
The feeding of other wild fish to these farmed animals contributes further to the problem of dwindling stocks, rather than helping to solve them, he believes. “To be fair, salmon farmers are searching for ways to be less dependent of wild fish as feed, substitutions which include genetically modified crops — which opens up a whole other debate.”
Amongst Roberts’s proposals is the establishment of a network of protected marine zones, as well as a ban on fishing beneath 800m and a phasing out of bottom trawling and dredge fishing. In 2010, his team at York University built a scientific case for the world’s first network of high seas marine reserves in the North Atlantic by placing 300,000 sq km of ocean under protection.
“Marine reserves protected from all fishing have had notable success in giving endangered species breathing room, but only .006% of the ocean is currently protected,” he says. “We need fifty times more reserve areas to do the job well, spread across the waters of coastal nations and the high seas.”
* Callum Roberts, West Cork Literary Festival, Tuesday, Jul 9, at 6.30pm.
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