Ocean Acidification

Fish, both big and small, suffering from overfishing, climate change, acidification, agricultural runoff — and U.S. taxpayer subsidies.

The onslaught of bad news about the world’s oceans continues.

We already have learned that overfishing at current rates will deplete 90% of the world’s commercial fish by mid-century. We’ve learned that ocean acidification, as the oceans absorb our carbon dioxide emissions, will bleach coral, prevent the plankton at the base of the food web from forming shells and ultimately compromise our food supply. We’ve learned that when you add up overfishing, acidification, pollution from agricultural and urban runoff and habitat destruction, it’s a recipe for returning the oceans to a primordial stew of algae and jellyfish.

Today, three new reports all paint the same picture.



The U.N. Food and Agriculture’s State of the World Fisheries and Aquaculture concludes that about 50% of all marine fish stocks are being “fully exploited” — meaning they are being fished at or near sustainable limits. Another 19% are overexploited, 8% depleted and 1% recovering from depletion.

Oceana, meanwhile, has released a report, Hungry Oceans (pdf), predicting the collapse of the ocean ecosystem because of overfishing of the smallest fish in the ocean. These prey species were considered so abundant, and so quick to replenish their own numbers, that depletion wasn’t a concern. We have proved that theory wrong, particularly as the world has begun catching more small fish — not only for direct human consumption, but to feed fish in aquaculture operations.

“We have caught all the big fish and now we are going after their food,” said Margot Stiles, marine scientist at Oceana. The result? “Widespread malnutrition in commercial and recreational fish, marine mammals, and seabirds.”

The loss of these forage fish — like herring, sardines and menhaden — threatens larger fish that eat them, like bluefin tuna, striped bass, Pacific salmon, and Pacific halibut, according to the report.

Finally, the most detailed financial analysis of its kind, by the Lenfest Ocean Program, finds that roughly half the $713 million in annual U.S. fishing subsidies contributes to overfishing by encouraging the targeting of overexploited fish stocks. Among the interesting other findings of the analysis: most subsidies come in the form of tax breaks on fossil fuels, and Western Pacific fishermen receive more than 20% of all subsidies, but catch just 2% of fish sold in the U.S

Dan Shapley, the daily green, 4 March 2009. Article.