New York Times, November 3, 2006
Study Sees 'Global Collapse' of Fish Species
By CORNELIA DEAN
If fishing around the world continues at its present pace, more and more
species will vanish, marine ecosystems will unravel and there will be
"global collapse" of all species currently fished, possibly as soon as
midcentury, fisheries experts and ecologists are predicting.

The scientists, who report their findings today in the journal Science, say
it is not too late to turn the situation around. As long as marine
ecosystems are still biologically diverse, they can recover quickly once
overfishing and other threats are reduced, the researchers say.

But improvements must come quickly, said Boris Worm of Dalhousie University
in Nova Scotia, who led the work. Otherwise, he said, "we are seeing the
bottom of the barrel."

"When humans get into trouble they are quick to change their ways," he
continued. "We still have rhinos and tigers and elephants because we saw a
clear trend that was going down and we changed it. We have to do the same in
the oceans."

The report is one of many in recent years to identify severe environmental
degradation in the world's oceans and to predict catastrophic loss of fish
species. But experts said it was unusual in its vision of widespread fishery
collapse so close at hand.

The researchers drew their conclusion after analyzing dozens of studies,
along with fishing data collected by the United Nations Food and
Agricultural Organization and other sources. They acknowledge that much of
what they are reporting amounts to correlation, rather than proven cause and
effect. And the F.A.O. data have come under criticism from researchers who
doubt the reliability of some nations' reporting practices, Dr. Worm said.

Still, he said in an interview, "there is not a piece of evidence" that
contradicts the dire conclusions.

Jane Lubchenco, a fisheries expert at Oregon State University who had no
connection with the work, called the report "compelling."

"It's a meta analysis and there are challenges in interpreting those," she
said in an interview, referring to the technique of collective analysis of
disparate studies. "But when you get the same patterns over and over and
over, that tells you something."

But Steve Murawski, chief scientist of the Fisheries Service of the National
Oceanic and Atmospheric Administration, said the researchers' prediction of
a major global collapse "doesn't gibe with trends that we see, especially in
the United States."

He said the Fisheries Service considered about 20 percent of the stocks it
monitors to be overfished. "But 80 percent are not, and that trend has not
changed substantially," he said, adding that if anything, the fish situation
in American waters was improving. But he conceded that the same cannot
necessarily be said for stocks elsewhere, particularly in the developing
world.

Mr. Murawski said the Bush administration was seeking to encourage
international fishery groups to consider adopting measures that have been
effective in American waters.

Twelve scientists from the United States, Canada, Sweden and Panama
contributed to the work reported in Science today.

"We extracted all data on fish and invertebrate catches from 1950 to 2003
within all 64 large marine ecosystems worldwide," they wrote. "Collectively,
these areas produced 83 percent of global fisheries yields over the past 50
years."

In an interview, Dr. Worm said, "We looked at absolutely everything - all
the fish, shellfish, invertebrates, everything that people consume that
comes from the ocean, all of it, globally."

The researchers found that 29 percent of species had been fished so heavily
or were so affected by pollution or habitat loss that they were down to 10
percent of previous levels, their definition of "collapse."

This loss of biodiversity seems to leave marine ecosystems as a whole more
vulnerable to overfishing and less able to recover from its effects, Dr.
Worm said. It results in an acceleration of environmental decay, and further
loss of fish.

Dr. Worm said he analyzed the data for the first time on his laptop while he
was overseeing a roomful of students taking an exam. What he saw, he said,
was "just a smooth line going down." And when he extrapolated the data into
the future "to see where it ends at 100 percent collapse, you arrive at
2048."

"The hair stood up on the back of my neck and I said, 'This cannot be true, " he recalled. He said he ran the data through his computer again, then did the calculations by hand. The results were the same.

"I don't have a crystal ball and I don't know what the future will bring,
but this is a clear trend," he said. "There is an end in sight, and it is
within our lifetimes."

Dr. Worm said a number of steps could help turn things around.

Even something as simple as reducing the number of unwanted fish caught in
nets set for other species would help, he said. Marine reserves would also
help, he said, as would "doing away with horrendous overfishing where
everyone agrees it's a bad thing; or if we banned destructive fishing in the
most sensitive habitats."

Josh Reichert, who directs the environmental division of the Pew Charitable
Trusts, called the report "a kind of warning bell" for people and economies
that depend on fish.

But predicting a global fisheries collapse by 2048 "assumes we do nothing to
fix this," he said, "and shame on us if that were to be the case."