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Fishing for Answers: Will the Oceans Run Out of Fish?

A recent two-week spate, of ominous oceanic fishing reports, has lent credence to the projection, from a group of scientists that the oceans will run out of fish within the next forty years.

The latest report was delivered on September 13, by the San Jose Mercury News “In an ominous environmental sign, California regulators this month closed all herring fishing in San Francisco Bay for the first time ever, shutting down the last commercial fishery in the Bay… Populations have been falling recently, and last year state scientists found herring numbers were down 90% from historic levels.”

last year state scientists found herring numbers were down 90% from historic levels.

That 90% figure is more ominous than it might seem. In a report published in Science Magazine in November of 2006, an international team of scientists concluded that a decline of 90%, of a species of fish in a marine system, can lead to a domino effect that can threaten all the marine life in that system. Boris Worm of Canada’s Dalhousie University said “Whether we looked at tide pools or studies over the entire world’s ocean, we see the same picture emerging. In losing species we lose the productivity and stability of entire ecosystems. I was shocked and disturbed by how consistent these trends are.”

The study was conducted at the National Centre of Ecological Analysis and Synthesis, at the University of California, over a four year period. The team researched the historical records of sixty-four oceanic regions across the globe, representing 83% of the fish species in the world. They also studied forty-eight marine reserves and fishing grounds. The scientists projected that the oceans would, baring significant changes, become barren of fish by 2048.

The recent string of bad news began on August 24, 2009, when the Atlantic States Marine Fisheries Commission, which regulates migratory fish on the eastern U.S. coast, announced they were considering a complete ban on harvests of weakfish, after weakfish stocks had hit an all-time low of three million pounds. And these stocks had fallen in spite of the fact that harvests had dropped over the last three decades. In 1980, the harvest of weakfish was eighty million pounds and by 1986 it had fallen to thirty-one million and in 1993 to eight million.

Further bad news came on August 28, when a group of scientists from the Scripps Institute of Oceanography, at the University of California, reported that a gigantic floating mass of trash had much more debris in it than expected. And some of the debris, including plastic, had broken down into bite-sized chunks that fish, birds and plankton had been ingesting, apparently killing some of them. The massive patch, commonly known as the Great Pacific Garbage Patch, is approximately half a million square miles in size and has been a matter of great concern for some time. The National Oceanic and Atmospheric Administration of the U.S. have estimated that 100 000 marine mammals die of trash-related deaths every year.

100 000 marine mammals die of trash-related deaths every year.

The bad news continued on September 10, when the UK Times Online, reported that researchers have concluded that cod in the North Atlantic are doomed to disappear because of rising water temperatures, brought on by climatic changes. If true, it could have a devastating impact on the English fishing industry.

On September 13, the New York Times reported that the New Zealand government had slashed the allowable catch of Hoki, from about 275 000 tonnes in 2000 and 2001 to about 100 000 tonnes in 2007 and 2008. The New Zealand Hoki fishery had been considered by many to be a showpiece of oceanic sustainability, but now that it has cut its harvest by almost two-thirds, that picture is fading. This failure has cast doubts on whether any ocean fishery can be considered truly sustainable in these days of environmental instability.

World-Wide Decline of Fish Stocks

The recent spate of bad news caps off a continuing series of ominous fishing reports this decade. In February 2002, after an oceanic survey, scientists warned that high-tech fishing was emptying the deep seas of fish and threatening their existence. The report stated that modern technology has enabled fishermen to harvest areas they previously had been unable to reach.

In 2003, a group of scientists reported that many large marine species like tuna, sharks, marlin, swordfish, cod and halibut had declined in numbers to only 10% of their historical levels. And these predators, so important in maintaining an ecological balance, were discovered to now be less than half as large as they used to be.

In March 2009, the Food and Agriculture Organisation of the United Nations reported that over 70% of fish species were currently endangered.

In March 2009, the Food and Agriculture Organisation of the United Nations reported that over 70% of fish species were currently endangered. After monitoring over 600 species of fish, they concluded that 52% of them were fully exploited, 19% were over-exploited and 8% were depleted.

In that same time period, Oceana released a report predicting that the ocean’s ecosystems will collapse if the over-harvesting of small fish like herring, sardines and menhaden continues.

Even though fish stocks have steadily dwindled over the years, commercial fishing companies haven’t shown much willingness to voluntarily lower their harvests. This isn’t surprising, because unless every fishing company across the globe agrees to limit their catch, the ones who do agree will place themselves at a competitive disadvantage. And even if every fishing company does agree to limit their harvests, the numerous illegal fishers won’t comply.

For health reasons, fish has gained popularity over the past two decades. The demand for fish has steadily climbed over the past three decades, even above the growth rates of populations and gross national products. Demand is expected to continue to rise, which means the price of fish will also rise. So even though it is getting harder and harder to find good fishing spots, the harvests will continue to be worth more and fishing will continue to be profitable. It’s going to be very difficult to limit worldwide harvests.

Environmental Factors

But limiting fish harvests might not guarantee the full recovery of fish. The cod fishery of Grand Banks of Newfoundland, once the world’s richest fishery, placed a moratorium on cod fishing in 1992, after cod stocks had dropped to dangerous levels. And today, though the moratorium is still in place, the cod have still not recovered. Many analysts believe that the ecology of the area has changed to the point where the cod may never recover.

Many scientists believe that climatic changes have caused problems for the fishing industry in many places throughout the world, though this has been difficult to prove conclusively. But it’s reasonable to assume that, if global warming continues, it will contribute significantly to the current environmental instability.

Environmental pollution has also caused major problems for the oceans. Several oil spills have devastated areas for many years. The oceans have grown increasingly more acidic, and some scientists project that by the end of the century the oceans will become more acidic than they’ve been in hundreds of millions of years, with potentially catastrophic effects on ecosystems.

A United Nations report in 2004 said that, the number of oceanic dead zones (oxygen-deprived areas where no fish or marine animals can survive) had steadily increased to about 150, some as large as 45 000 square miles. One of the main causes of the dead zones is nitrogen run-off from chemical fertilisers.


Many people believe that aquaculture, or fish farming, is a potential solution to future fish demand. In 1980, aquaculture accounted for 9% of the world’s fish production by weight, and by 2005 that percentage had grown to 43%. If that number surprises you, it’s because over 90% of that aquaculture occurred in Asia, mostly in small ponds.

Large commercial fish farms are not without problems, especially those in the oceans. Most farms in North America use cages for their fish that aren’t closed off from the ocean environment and because the waste treatment at most of these farms is inadequate, nitrogen from fish wastes builds up and leaches out into the surrounding ocean, creating dead zones around the fish farms. And there have been incidents where sea lice—common in salmon farms—have spread from caged salmon to wild salmon, killing up to 95% of the juvenile wild salmon in the area.


On the other hand, the small aquaculture farms of Asia have proven successful for thousands of years. Their methods may seem antiquated to the modernised fishermen in technologically advanced countries, but perhaps they have something to teach the rest of us.