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ENVIRONMENT:
New Historical
Data on the Seas Spells Alarm
Stephen
Leahy*
TORONTO, (Tierramérica) -
New historical data reveal that
the world's oceans are in
crisis, largely due to
overfishing -- and they may not
recover.
The records indicate that the
existing model for commercial
fishing will exhaust fisheries
in a decade or two.
"The oceans are dramatically
different than they were 150
years ago," said Poul Holm, a
scientists with the Centre for
Maritime and Regional Studies at
the University of Southern
Denmark.
Back then, "there were many more
top predatory fish like tuna,
and nearly all fish were much
larger... and found over wider
areas than today," Holm told
Tierramérica.
Several hundred historians and
marine scientists from around
the world have been conducting
research for more than five
years into what the oceans were
like 150, and even 300 years
ago. They presented their
findings last week at the
History of Marine Animal
Populations "Oceans Past"
Conference in Kolding, Norway.
Historical records revealed for
example that the ling cod (Molva
molva) of the North Sea had been
fished out before 1920, when the
decline was previously believed
to have started in the 1970s.
Fisheries data only goes back a
few decades so it is difficult
to know the true extent of the
crisis or to be able to manage
remaining stocks without
information from the era before
large-scale industrial fishing,
Holm said.
"Just as important as changes in
fish stocks, we need to know how
the marine ecosystem has
changed."
Even without direct fishing
pressure, the ling cod, the
northern cod and other species
have not recovered, suggesting
that fundamental ecological
changes have occurred.
What this new data on the
history of the oceans makes
clear is a pattern of commercial
fishing that depletes one stock
in a decade or two and then
moves on to the next, and then
the next.
That pattern is evident among a
collection of 200,000 U.S.
restaurant menus, dating back to
the 1860s.
In the 1870s, 20-pound lobsters
were so common that they were
canned and rarely found on
menus. "It was considered a
trash fish no one wanted -- it
was not something you'd want to
be seen eating," said Glenn
Jones at Texas A&M University in
Galveston, Texas.
As more favored species
declined, lobster found its way
onto menus, and by the 1920s was
priced at an average of 24
dollars a pound -- about the
same price as today, Jones said
in a Tierramérica interview.
Lobster sizes dropped to a
half-pound, the minimum for
harvest, but their stocks are
not endangered.
"Lobsters are one of the best
managed marine resources we
have," he said. Larger four- and
five-pound lobsters have been
showing up on menus in the last
decade, a sign that new deep-sea
areas on the outer continental
shelf, 200 miles offshore are
now being harvested, Jones said.
"Within 10 years those large
ones will be gone too," he
predicted.
Abalone (Haliotis rufescens), a
tasty, slow-growing mollusc from
the seas off California's coast
followed a similar pattern.
Popular in the 1920s and priced
at about seven dollars for a
meal in today's currency, as the
species was increasingly
overfished, prices rose seven to
10 times faster than inflation
by the 1950s.
California banned commercial
abalone fishing in 1997. Most
abalone in California
restaurants today is imported
from Australia and New Zealand
and priced at 50 to 70 dollars a
portion.
The importance of having a
long-term data set is
illustrated by a study of
Mexican fishers from the Gulf of
California, on the western coast
and inside Baja California
peninsula.
Compared to the average
30-year-old in the business,
those who were over 55 could
name five times as many depleted
sites and five times as many
fish species that had
disappeared, according to Andrea
Saenz-Arroyo at the University
of York in England.
Those 30-year-old fisherfolk
were unaware that the seas they
had fished all their lives were
once abundant with sharks, huge
groupers, snappers, green
turtles, rock oysters and conch.
"There was a dramatic shift in
perception of what constitutes
the natural state of the
environment," Saenz-Arroyo told
Oceans Update, a newsletter from
SeaWeb, a Washington-based
educational non-governmental
organisation.
Three hundred years before the
older fisherman were born, the
Gulf of California was
remarkably different, with heaps
of pearl oysters lying about,
according to Spanish explorers.
Goliath groupers were a common
and favoured meal back then, but
no fisherman of any age today
knew they once swam there.
People fail to appreciate the
scale of environmental
degradation in their own
lifetimes she said.
And that reduces expectations of
what constitutes a "healthy"
ecosystem.
"An understanding of past
environmental conditions is
essential for effective
conservation today," said
Saenz-Arroyo.
Short memories and the twin
myths of abundance and endless
seas keeps enlarging the global
fishing fleet, despite much
evidence that a crisis is at
hand.
Even wide-ranging species like
the Atlantic bluefin tuna (Thunnus
thynnus), which were found in
abundance from northern Norway
to the Black Sea, and from
Newfoundland to southern Brazil,
have vanished from half of this
vast area.
Although fished for several
centuries, the Atlantic bluefin
tuna decline is the result of
the development of new fishing
equipment and technologies
during the mid-1900s. Moreover,
modern fishing practices and
regulations (such as intentional
and unintentional capture of
immature fish, mis- and
non-reporting of catches) are
reducing the likelihood that
bluefin tuna will recover,
experts reported at the
conference.
The global output of fish and
seafood has been in decline for
some years, despite an
ever-increasing effort to catch
fish, said Holm.
"The demand for fish is well
beyond what the oceans can now
provide."
The continuing pattern of
pursuing new species after other
stocks fail is now endangering
the slow-growing Patagonian
toothfish and Chilean sea bass.
Pirate fishing boats illegally
net millions of dollars worth of
these fish and sell them on the
black market.
"Global governance over the
deep-sea regions is badly
needed," concludes Holm.
(*Originally published Oct. 29
by Latin American newspapers
that are part of the
Tierramérica network.
Tierramérica is a specialised
news service produced by IPS
with the backing of the United
Nations Development Programme
and the United Nations
Environment Programme.
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