Fishing industry's slaughter leaves legacy of empty seas

By STEVE CONNOR

Industrialised fishing has taken 90 per cent of the world's biggest ocean fish over the past 50 years, says a study published yesterday.

The scale of the loss has astounded fisheries experts who had thought the oceans were still teeming with "sea monsters", such as giant marlin, tuna and swordfish.

Using data gathered over 10 years, two scientists have exploded the myth that the oceans are still under-exploited.

Ransom Myers, a marine biologist from Canada's Dalhousie University in Halifax, Nova Scotia, said it took between 10 and 15 years for industrialised fishing to reduce any new fish community it found to a tenth of what it was before.

"From giant blue marlin to mighty bluefin tuna, and from tropical groupers to Antarctic cod, industrial fishing has scoured the ocean," he said.

Working with Boris Worm of the University of Kiel in Germany, Dr Myers investigated four continental shelves and nine open-ocean regions.

"Since 1950, with the onset of industrialised fisheries, we have reduced the resource base to less than 10 per cent - not just in some areas, not just for some stocks, but for entire communities of these large fish species from the tropics to the poles," Dr Myers said.

The researchers, who published their findings in the journal Nature, also gained access to data about Japanese longline fishing - lines armed with thousands of hooks which trail for miles.

Longline fishing is the most widespread fishing technique, and the Japanese fleet is the most widespread longline operation covering all oceans apart from those around the poles.

The decline in the longline catch showed how severely fish stocks had been depleted, the two scientists said.

"Where longlines used to catch 10 fish per 100 hooks, now they are lucky to catch one," Dr Myers said.

Dr Jeremy Jackson, of the Scripps Institution of Oceanography in the US said that as well as fish numbers declining, the average size of fish caught today was far smaller than those landed in the past.

"We had oceans full of heroic fish, literally sea monsters," he said.

"People used to harpoon three-metre-long swordfish in rowboats. Hemingway's Old Man and the Sea was for real."

Dr Myers says top marine predators are on average only a fifth to a half of the size they once were.

"The few blue marlin today reach one fifth of the weight they once had. In many cases, the fish caught today are under such intense fishing pressure, they never even have the chance to reproduce."

He and Dr Worm blame high fishing quotas, better fishing technology - such as satellites and sonar - government subsidies and a dearth of marine reserves for the drastic decline in fish.

They want a cut of at least 50 per cent in the number of fish being caught.

"We continue to bicker over the last shrinking numbers of survivors, employing satellites and sensors to catch the last fish left," Dr Myers said.

"We have to understand how close to extinction some of these populations are. And we must act now, before they reach the point of no return."

- INDEPENDENT