Clambakes, crabcakes, swordfish steaks and even humble fish sticks could be little more than a fond memory in a few decades.
If
current trends of overfishing and pollution continue, the populations
of just about all seafood face collapse by 2048, a team of ecologists
and economists warns in a report in Friday's issue of the journal
Science.
"Whether we looked at tide pools or studies over the
entire world's ocean, we saw the same picture emerging. In losing
species we lose the productivity and stability of entire ecosystems,"
said the lead author Boris Worm of Dalhousie University in Halifax,
Nova Scotia.
"I was shocked and disturbed by how consistent these trends are -- beyond anything we suspected," Worm said.
While
the study focused on the oceans, concerns have been expressed by
ecologists about threats to fish in the Great Lakes and other lakes,
rivers and freshwaters, too.
Worm and an international team spent
four years analyzing 32 controlled experiments, other studies from 48
marine protected areas and global catch data from the U.N. Food and
Agriculture Organization's database of all fish and invertebrates
worldwide from 1950 to 2003.
The scientists also looked at a
1,000-year time series for 12 coastal regions, drawing on data from
archives, fishery records, sediment cores and archaeological data.
"At
this point 29 percent of fish and seafood species have collapsed --
that is, their catch has declined by 90 percent. It is a very clear
trend, and it is accelerating," Worm said. "If the long-term trend
continues, all fish and seafood species are projected to collapse
within my lifetime -- by 2048."
"It looks grim and the projection
of the trend into the future looks even grimmer," he said. "But it's
not too late to turn this around. It can be done, but it must be done
soon. We need a shift from single species management to ecosystem
management. It just requires a big chunk of political will to do it."
The researchers called for new marine reserves, better management to prevent overfishing and tighter controls on pollution.
In
the 48 areas worldwide that have been protected to improve marine
biodiversity, they found, "diversity of species recovered dramatically,
and with it the ecosystem's productivity and stability."
