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July 16, 2003-5
Copyright © 2003 Earth Policy Institute
Other Fish in the Sea,
But
For How Long?
Janet Larsen
A recent review of marine fisheries
concluded that a startling 90 percent of the world's large predatory
fish, including tuna, swordfish, cod, halibut, and flounder, have
disappeared in the past 50 years. This 10-year study by Ransom Myers
and Boris Worm at Canada's Dalhousie University attributes the decline
to a growing demand for seafood, coupled with an expanding global
fleet of technologically efficient boats.
Once thought to be inexhaustible, the world's
fisheries are now showing their vulnerability. The United Nations
Food and Agriculture Organization (FAO) estimates that three quarters
of the world's oceanic fisheries are being fished at or beyond their
sustainable yields. The innovations that have allowed us to pull
more fish out of the oceans—larger
and more-powerful boats (some with on-deck processing facilities),
improved fishing gears, and navigational and fish-finding technologies—may
undermine the oceans' presumed resilience.
Data show that once large boats target a
fishery, they can deplete populations in a matter of years. Within
15 years, some 80 percent of the large fish are lost. Smaller species
may initially flourish, but often their populations soon crash too,
either because of a limited food supply, overcrowding, and disease
or because they become targets for those who are "fishing down the
food web." The average size of top predatory fish is now only one
fifth to one half that in the past, in part because the fish left
to breed are the ones small enough to escape from nets. Another
problem is that slow-maturing fish are often caught before they
are old enough to reproduce.
Fishing gears are frequently indiscriminate.
Trawlers drag enormous nets over a vast area, virtually clearcutting
the seabed, destroying marine habitat, and taking up untargeted
species. Worldwide, almost one fourth of the fish catch is discarded
dead at sea, either because the fish are not marketable or because
fishers have exceeded their catch allotment. Whales, dolphins, and
porpoises also become part of this collateral damage. In certain
fisheries, like the Gulf of Mexico shrimp fishery, the weight of
this "bycatch," as it is known, may exceed that of the profitable
take by 10 to 1.
After growing steadily for decades, the
world fish catch has stalled between 85 million and 95 million tons
since 1986. (See ).
In 2001, the world's fishing fleets landed some 92 million tons
of fish, according to FAO data. An analysis by Reg Watson and Daniel
Pauly at the University of British Columbia reveals that overreporting
by China, the world's largest fisher, and climate—related
fluctuations in Peruvian anchoveta populations may have masked an
actual decline in the global catch of some 660,000 tons per year
since 1988.
From 1950 to 1988, the world fish catch
climbed from 19 million to 89 million tons. This fivefold expansion
dwarfed the growth in global beef production during that period
(from 19 million to 54 million tons). In per capita terms, the annual
fish catch per person peaked at 17 kilograms in 1988, up from 8
kilograms in 1950. For most of the last half-century, we could count
on a steadily growing oceanic catch to help meet the growing demand
for animal protein. That era is over.
Prospects for the 1 billion people throughout
the world who rely on fish as their primary source of protein and
the 200 million involved with fishing and fish-related industries
rest on careful management of wild fish stocks and farms. Ecologists
liken fish stocks to a bank account. With a certain balance preserved
in the bank, we can live off of the interest. But if we continue
to dip into the principal, eventually we are left with an empty
account.
The collapse of the Newfoundland cod fishery
is a case in point. For centuries it was one of the world's most
productive fisheries, yielding 800,000 tons of fish and employing
40,000 people at its peak in 1968. Then its stocks plummeted as
a result of overharvesting and habitat damage. In 1992, the fishery
was closed in an effort to save it. But it may have been too late:
a decade has passed, but stocks have not recovered.
This collapse was local in scale, but the
issue is much larger. Fisheries operating over the entire North
Atlantic Ocean now catch half as many of the popular species—such
as cod, tuna, flounder, and hake—as
50 years ago, despite tripling their efforts. Cod stocks in the
North Sea and to Scotland's west are on the verge of collapse. In
a 2001 report entitled Now or Never: The Cost of Canada's Cod
Collapse and Disturbing Parallels With the UK, Malcolm MacGarvin
urges Europe to avoid the same fate as Newfoundland's fishers.
The deterioration of oceanic fisheries can
be reversed. Granting fishers an ownership stake in fish stocks
is one way to help them understand that the more productive their
fishery is, the more valuable their share. For example, fishers
in Iceland and New Zealand have used marketable quotas, allowing
them to sell catch rights, since the late 1980s. The upshot is smaller
but more profitable catches and rebounding fish populations. The
classic "tragedy of the commons" problem is averted.
Because of the complexity of marine ecosystems,
some scientists are pushing for management of whole ecosystems rather
than single species. In addition, studies have shown that well-positioned
and fully protected marine reserves, known as fish parks, can help
replenish an overfished area. By giving fish a refuge to breed and
mature in, reserves can increase the size and total number of fish
both in the reserve and in surrounding waters. For example, a network
of reserves established off St. Lucia in 1995 has raised the catch
by adjacent small-scale fishers by up to 90 percent. Preservation
of nursery habitats like coral reefs, kelp forests, and coastal
wetlands is integral to keeping fish in the sea for generations
to come.
Consumers can promote healthy fishery production
by eating less fish and buying seafood from well-managed, abundantly
stocked fisheries. The Seafood Lover's Guide from Audubon's Living
Oceans program is one valuable reference. Chilean seabass, for example,
makes the list of fish to avoid because stocks are on the verge
of collapse and illegal fishing abounds. The list also distinguishes
between wild Alaska salmon, which comes from a healthy fishery,
and farmed salmon, which is fed meal made from wild fish and thus
does not relieve pressure on marine stocks. Proper labels are needed
to allow consumers to make wise purchasing decisions. The Marine
Stewardship Council, a new independent international accreditation
organization, has thus far certified seven fisheries as being sustainably
managed with minimal environmental impact.
The capacity of the world's fishing fleet
is now double the sustainable yield of fisheries. Myers and Worm
from Dalhousie University believe that the global fish catch may
need to be cut in half to prevent additional collapses. Reducing
bycatch, creating no-take fish reserves, and managing marine ecosystems
for long-term sustainability instead of short-term economic gain
are all policy tools that can help preserve the world's fish stocks.
If these are coupled with a redirection of annual fishing industry
subsidies of at least $15 billion to alternatives such as the retraining
of fishers, there could be a big payoff. It is difficult to overestimate
the urgency of saving the world's fish stocks. Once fisheries collapse,
there is no guarantee they will recover.
Copyright
© 2003 Earth Policy Institute
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FOR ADDITIONAL INFORMATION
From Earth Policy Institute
Janet Larsen, "Fish
Catch Leveling Off," in Lester R. Brown, Janet Larsen, and Bernie
Fischlowitz-Roberts, The
Earth Policy Reader (New York: W.W. Norton & Company, 2002).
Lester R. Brown, "Fish Farming May Soon Overtake
Cattle Ranching as a Food Source," Eco-Economy
Update, 3 October 2000.
From Other Sources
Audubon's Living Oceans Program, Seafood
Lover's Guide (Islip, NY: 2000).
U.N. Food and Agriculture Organization, The
State of World Fisheries and Aquaculture (Rome: 2002).
Jeffrey A. Hutchings, "Collapse and Recovery of
Marine Fishes," Nature, vol. 406, 24 August 2000, pp. 882-85.
Jeremy B.C. Jackson et al., "Historical Overfishing
and the Recent Collapse of Costal Ecosystems," Science, vol.
293, 27 July 2001, pp. 629-38.
Malcolm MacGarvin, Now
or Never: The Cost of Canada's Cod Collapse and Disturbing Parallels
With the UK (Surrey, UK: WWF-UK, October 2001).
Lance E. Morgan and Ratana Chuenpagdee, Shifting
Gears: Addressing the Collateral Impacts of Fishing Methods in U.S.
Waters (Washington, DC: Island Press, 2003).
Ransom A. Myers and Boris Worm, "Rapid Worldwide
Depletion of Predatory Fish Communities," Nature, vol. 423,
15 May 2003, pp. 280-83.
Rosamond L. Naylor, et al. "Effect of Aquaculture
on World Fish Supplies," Nature, vol. 405, 29 June 2000,
pp. 1017-24.
Stephen R. Palumbi, Marine
Reserves: A Tool for Ecosystem Management and Conservation
(Arlington, VA: Pew Oceans Commission, 2003).
Les Watling and Elliott A. Norse, "Disturbance of
the Seabed by Mobile Fishing Gear: A Comparison to Forest Clearcutting,"
Conservation Biology, vol. 12, no. 6, December 1998, pp.
1180-97.
Reg Watson and Daniel Pauly, "Systematic Distortions
in World Fisheries Catch Trends," Nature, vol. 414, 29 November
2001, pp. 534-36.
LINKS
Audubon's Living Oceans Project
http:/www.audubon.org/campaign/
lo/seafood/
U.N. Division for Ocean Affairs and the Law of the
Sea
http:/www.un.org/Depts/los
Environmental Defense's Seafood Selector
http:/www.environmental
defense.org/seafood/fishhome.cfm
FishBase
http:/www.fishbase.org
U.N. Food and Agriculture Organization (FAO) Fisheries
Department
http:/www.fao.org/fi
The Marine Fish Conservation Network
http:/www.conservefish.org
The Marine Stewardship Council
http:/www.msc.org
OneFish Fisheries Research Portal
http:/www.onefish.org
Pew Oceans Commission
http:/www.pewoceans.org
The Sea Around Us Project
http:/saup.fisheries.ubc.ca
Seafood Choices Alliance
http:/www.seafoodchoices.com
SeaWeb
http:/www.seaweb.org
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