Science - Reuters
Scientists: Only 10 Percent of Big Ocean Fish Left
Wed May 14, 3:14 PM ET
By Patricia Reaney
LONDON (Reuters) - 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 on Wednesday.
"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 immortalized 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 compromised.
"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
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 is published in the science journal
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 dinosaurs.