10 percent of big ocean fish left - scientists
UK: May 16, 2003
LONDON - Large predatory fish - marlin, tuna and
swordfish - are disappearing from the world's oceans,
with their numbers down by 90 percent in the past 50
years, Canadian scientists said.
"From giant blue marlin to mighty blue fin tuna, and from
tropical groupers to Antarctic cod, industrial fishing has
scoured the global ocean," said Ransom Myers, a biologist
at Dalhousie University in Canada.
"There is no blue frontier left."
Myers and his colleague Boris Worm estimate that
compared with when industrial fishing began in the
1950s, less than 10 percent of large predatory fish species,
the old men of the sea, have survived.
"This means that the larger, more sensitive species like
the sharks will go extinct unless we reduce fishing in a
very large-scale manner," Myers said in an interview.
The great fish, like the one immortalised in Ernest
Hemingway's "Old Man and the Sea" are not only dwindling
in numbers, they are also getting smaller.
Top predator fish are about one fifth to one half the
size they used to be. Many fish never get the chance to
reproduce, according to the researchers.
People had presumed there were untapped reservoirs of
large fish, but Myers said that is not true. He warned
that the sustainability of fisheries worldwide is being
"This calls for a reduction in fishing worldwide so we
can allow the natural diversity and fish species to persist
in the world's oceans," he said.
"A minimum reduction of 50 percent of fish mortality
(the percentage of fish killed each year) may be necessary to
avoid further declines of particularly sensitive species."
As well as the big predators, there are also fewer large
ground fish such as cod, halibut, skate and flounder.
In a 10-year study, Myers and Worm examined data from
fisheries and scientific research institutes to estimate the
number of fish remaining in the world's oceans.
"It is a worldwide analysis...to find out what is
happening in the world's oceans," said Myers, whose research
published in the science journal Nature.
If stocks are restored, he added, fishermen could get
more fish out of the oceans with a fraction of the effort. If
they aren't, the great fish will suffer the fate of the
Story by Patricia Reaney
REUTERS NEWS SERVICE