Fish Decline Must Stop, Experts Say

Marine biologist and deep-sea diver Sylvia Earle recalled that studies conducted in the Bahamas to curb Japanese commercial fishing showed that a swordfish that is caught and released repeatedly can bring the sports fishing industry $27,000. But sold to a fish market, it is only worth $20.

"We look at fish as a commodity and the oceans as supermarkets," complained Earle, who was dubbed "Sturgeon General" at her previous position as chief marine scientist at the National Oceanic and Atmospheric Administration (NOAA), a U.S. federal agency.

When a shark fin is worth 50 times more than the rest of the carcass, fish workers often slice off the fins and toss the shark back into the water to die a slow death. Sharks are also killed for meat, leather, teeth and for their cartilage, which is used as a treatment for anything from cancer to the common cold.

In 1989, an estimated 100 million sharks were killed worldwide. Today, shark populations are the lowest they have been in 450 million years, according to Carl Safina, director of the National Audubon Society's Living Oceans Program.

"I do believe it's okay to use what's in the oceans but not to use it up," said Safina, formerly a commercial fisherman.

The United Nations Food and Agriculture Organization (FAO) has warned that fisheries are on the decline worldwide, with virtually every commercial fish species "over-exploited," "fully exploited," or "depleted." Fish species are being taken from the seas faster than they can regenerate.

In a quarter of the world's marine fishing regions, the catch has shrunk by more than 30 percent, according to the Washington-based Worldwatch Institute. But, says the Institute's Peter Weber, "Fishers could potentially increase their catch by 20 million tons -- 25 percent of the current catch -- if they allowed fish populations to rebuild."

Worldwatch also estimates that more than 100,000 fish workers lost their jobs in the last few years because of declining catches. Depleted resources have led to heavy competition and even to international skirmishes.

Some of the wrangles over scarce resources have pitted Canadian fish interests against those in the United States. Spain and Canada have clashed, as have Norway and Iceland, and Argentina and Taiwan.

"It's as if peace has been declared on land and war in the oceans," said Safina.

In addition to overfishing, pollution from the discharge of oil and chemical contaminants has taken a huge toll on global marine fish populations. Coastal regions are particularly affected by pollution. Some 90 percent of the world's fish catch comes from the third of the oceans near the coasts.

A quarter to a third of the world's catch is also discarded by fish workers as "by kill," endangering some species.

Non-traditional fishing methods, including the use of satellites, sonar, high-intensity lights and cyanide, which is used to temporarily stun fish are also endangering species. Nylon fishing nets, weighed down by chains and dragged along the seabed also kill sea urchins, crustaceans, and starfish.

"These things have turned oceans into underwater minefields for fish," said Safina.

Fish and other sea products also supply 16 percent of animal protein consumption globally. And according to Worldwatch, one billion people in Asia rely on fish as a primary source of protein.