Great White Sharks Among
Glen Martin, Chronicle Staff Writer
More than 80 species of North American fish are in danger
of extinction, primarily due to overfishing and habitat
destruction, a new study has found.
Thursday, November 2, 2000
The report concludes that many California fish generally
thought of as common are at particularly grave risk,
including great white sharks and several species of
Environmentalists say the study, which appears in the
current issue of Fisheries, a peer-reviewed scientific
journal published by the American Fisheries Society,
demonstrates an immediate need for an extensive marine
refuge system where fishing would be permanently
``The big message from this is that we have the power to
permanently remove large numbers of species from the
oceans,'' said Kate Wing, an ocean policy analyst with the
Natural Resources Defense Council.
``We think the ocean is so vast that we can't exterminate
its (fish), but that's precisely what we're doing.''
In all, the report identifies 82 species of marine and
estuarine fish living in the waters off Canada, the United
States and Mexico that are in danger of extinction.
Overfishing was the root cause of the threat in most cases,
followed by habitat destruction and pollution.
The report has special significance for California, which
supports one of the richest and most biologically diverse
marine fisheries in the world. The data was particularly
ominous for rockfish, a complex of bottom-dwelling food
and sport fish that number in the scores of species.
Twelve rockfish of the genus Sebastes were listed as
threatened with extinction, along with lingcod, another
botton-dwelling fish noted for its large size, ferocious
fighting ability and succulent flesh.
Several sharks were also listed, including great white
sharks and basking sharks, both found off California. Great
whites are the largest piscine ocean predator, and are often
observed killing seals and sea lions off the Farallon
Islands near San Francisco and Ano Nuevo Island north
of Santa Cruz.
Basking sharks are the second biggest fish in the world.
Only whale sharks are larger -- and they also made the
Four types of sturgeon were also listed, including the
white sturgeon and green sturgeon, both found in San
The study is surprising, given that many of the listed
species are popular in fish markets and with sport anglers.
Rockfish and sturgeon are commonly caught by Bay Area
Fish scientists say most of the listed species share
``They tend to be slow-growing. They're slow to reach
sexual maturity. They have low fecundity. And that all
means they tend to have low rates of population growth,''
said John Edward Olney, an associate professor with the
Virginia Institute of Marine Science, which is associated
with the College of William and Mary.
Olney said the misperception that many of the threatened
fishes are common is due to ``occasional local pockets of
abundance. But it's important to realize these are basically
relict populations, residuals left from populations that were
once much, much larger.''
Rebuilding populations of the depleted fish may be
difficult, fisheries experts say, and will only succeed if
there is long-term commitment.
``The Pacific Fishery Management Council (which
establishes marine fishing regulations in federal waters) is
working on a recovery plan for cow cod (a large Pacific
rockfish), and they're figuring it will take 90 years because
their populations are so low,'' Wing said. ``And at the end
of that time, there's no guarantee the plan will work.''
Wing said it is imperative to establish marine refuges
immediately. This, she said, will help stabilize current
populations of threatened species.
``We basically need large reserves, areas where fishing is
prohibited,'' she said. ``Marine refuges allow large numbers
of fish to congregate in protected circumstances so they
can breed successfully. They produce eggs and larvae
that migrate outside the reserve borders, reseeding other
But some fishing industry advocates think other
approaches might be better.
``Refuges are not going to help a lot of these stocks,'' said
Zeke Grader, the executive director of the Pacific Coast
Federation of Fishermen's Associations. ``They're
everybody's favorite mantra right now. They might work
for certain species of rockfish, but what we really need is a
combination of good research followed by sound
Grader said fish stocks should be ``proactively protected
and rebuilt. That includes making sure we really have good
information on the life histories of the (threatened
species), and perhaps prohibiting certain types of
activities, like heavy bottom trawling. We should also look
at restoring habitat, like building artificial reefs where
natural ones have been destroyed.''
E-mail Glen Martin at email@example.com.