Sea
Turtle Is Losing the Race
The
leatherback has outlasted the dinosaurs but is unlikely to
survive poachers and fishing gear. Its decline signals
peril for the Pacific too
By
Kenneth R. Weiss, Latimes.com
PLAYA GRANDE, Costa Rica --
The leatherback sea turtle, the massive and mysterious
reptile of the Pacific Ocean, has outlived the dinosaurs
by 65 million years. It has survived fiery asteroid
strikes and ice ages that chilled the globe.
But it doesn't look as if this prehistoric innocent will
survive us.
Beset by poachers on land and snared in fishing gear at
sea, the Pacific Ocean's population of leatherbacks has
plunged 95% in the last 22 years, scientists say. They
estimate that fewer than 5,000 nesting females remain in
the Pacific.
"I never thought this ancient creature would be
vulnerable to extinction," said Larry Crowder of the
Duke University Marine Lab. "Unless something
changes, the Pacific leatherback will be extinct within 10
to 30 years."
Scientists, once focused on protecting turtle nests on
shore, are shifting their attention to what they see as a
greater menace: the drowning of turtles in fishing nets
and on strings of baited hooks unfurled for 50 miles off
the sterns of commercial long-line vessels.
Crowder calculates that long-line fishermen set 4.5
million hooks every night, stringing the ocean with the
marine equivalent of 100,000 miles of barbed-wire fencing.
Alarmed by the precipitous decline of leatherbacks, more
than 400 scientists recently called on the United Nations
to ban coastal drift nets and pelagic long-lining for
swordfish until the gear can be modified to reduce turtle
deaths.
The United Nations has yet to take up the cause, which is
certain to stir opposition from the fishing industry.
Fishermen insist that they don't target sea turtles, that
the air breathers are inadvertently caught in nets or
snagged by hooks and then drown when they cannot reach the
surface to breathe.
Scientists and conservationists are pushing hard to reduce
wasteful practices in commercial fishing fleets, which,
besides drowning turtles, inadvertently catch and kill
seabirds, dolphins, sharks, marlin and many other types of
fish that are discarded.
They also see the looming demise of the Pacific
leatherback as a warning sign that the world's largest
ocean is in trouble. Leatherbacks range so widely and are
so dispersed in the Pacific that scientists never
previously considered their population capable of
collapse.
Now they realize that the vast Pacific has limits and that
its marine life has limited resilience and is proving no
match for burgeoning international fishing fleets.
'Way Overfished'
"The Pacific is the Wild West: It's way overfished by
these huge fleets, especially from Asia, and there are no
regulations at all," said Frank V. Paladino, chairman
of the biology department at Indiana-Purdue University.
"I keep trying to stress, it's not just sea turtles.
Everything is going in the Pacific. Sharks. Dolphins.
Billfish. The leatherbacks are just first to go."
Aside from lobbying for changes in global fishing
practices, Paladino and other turtle researchers follow
female turtles, gathering up their eggs as they are laid
and reburying them in safer parts of the beach.
Paladino and James V. Spotila, a zoologist at Drexel
University, pay rangers at Las Baulas National Park to
protect the turtles from poachers by patrolling the beach
here on Costa Rica's Pacific shoreline from dusk to dawn.
Using grants, donations and tourism dollars, they also run
a leatherback hatchery to boost the remnant turtle
population. Only one in 1,000 hatchlings makes it to
adulthood. They figure they can improve the odds to 1 in
100 by incubating the eggs in the hatchery and fending off
predators such as raccoons, skunks and dogs.
"We never intended to do all this," Spotila
said. "But you study this magnificent animal and you
see it going extinct, if you don't step in and do
something. It's like the kid walking by the dike with a
leak in it. You stick your finger in it. Then you cannot
very well leave."
The leatherback, the largest and oldest of the sea
turtles, has been around 100 million years or so —
surviving the asteroid that 65 million years ago struck
the Yucatan Peninsula, which scientists believe
contributed to the extinction of the dinosaurs.
Leatherbacks, though contemporaries of the dinosaurs, are
reptiles and feed predominantly on another ancient
creature: jellyfish.
The turtle gets its name from a leathery shell that has
the texture of smooth, hard rubber. Its shell also has
hydrodynamic dorsal ridges, which, combined with front
flippers that can span 10 to 15 feet, enable these
reptiles to soar like giant birds through the ocean.
Leatherbacks dive deeper than hard-shelled turtles —
nearly a mile — because their supple shells can compress
under the intense pressure. They also venture into colder
waters because of an ability to regulate their body
temperature.
Males spend their entire lives at sea, making them
particularly difficult to study. The biggest male on
record was 9½ feet long and tipped the scales at nearly a
ton. Females are smaller. Once they reach maturity, they
venture ashore every three years, on average, to lay their
eggs. That nesting routine provides researchers their only
real opportunity to study these ancient animals.
Paladino and Spotila have been studying nesting
leatherbacks in Costa Rica since the 1980s. In 1988, they
tallied 1,367 turtles nesting on Playa Grande, one of the
four largest nesting colonies in the world. By 1995, the
number had dropped to 506. This year, it was only 59, and
they predict the colony could vanish altogether within a
decade or so.
Hope in Indonesia
Nesting beaches in Mexico are in worse shape. Fewer than
50 turtles showed up on four beaches where there once were
thousands. Malaysia, another major nesting site, saw only
two this year. Indonesia offered a bit more hope this
year, with hundreds of nesting females emerging from the
ocean to lay eggs.
Leatherbacks in the Atlantic Ocean appear to be more
stable, for now.
Initially, scientists figured the biggest threats came
from poachers who slaughtered turtles for their meat or
stole the eggs to be sold for reputed aphrodisiac
qualities. Scientists supported the ban on harvesting of
turtles and their eggs, and then pursued the trickier task
of enforcing the law in poor countries.
Then turtle researchers started charting the remarkable
range of leatherbacks with satellite tracking tags. They
soon discovered that the leatherbacks in Mexico and Costa
Rica swam south around the Galapagos Islands and into the
drift nets positioned by fishermen like enormous fences
off the coast of Peru and Chile.
"The satellite tags gave us an inkling that the
problem wasn't just on the beaches, but on the high
seas," said Scott Eckert, a San Diego-based sea
turtle researcher. He calculates that these gill nets,
designed to catch swordfish, killed between 2,000 and
3,000 leatherbacks every year from 1982 to the mid-1990s.
The United Nations has since banned gill nets more than
one mile long in international waters, but smaller ones
continue to snag turtles. In the global hunt for
swordfish, mahi-mahi and shark fins (for shark fin soup),
most of the nets have now been replaced by long-line
fishing.
More boats from China, Taiwan, Korea, Japan and Spain join
the Pacific long-line fleet every year, each unfurling
lines of baited hooks of at least 50 miles.
Leatherbacks bite only occasionally at the hooks baited
with squid. Mostly they get tangled in the lines or snag
flippers on hooks and then drown.
To protect leatherbacks around Hawaii, the Turtle Island
Restoration Network of Forest Knolls, Calif., sued in
federal court and shut down the U.S. swordfish long-line
industry around the islands. About 30 of the boats moved
to Southern California to escape the ban, but
conservationists filed another lawsuit to close those down
too. The case is pending in federal court.
Scott Barrows, general manager of the Hawaii Longline
Assn., complains that the ban, instead of protecting
turtles, simply created an opening for less cautious
fishermen from Asia. "They took us out and allowed
the foreign fleet to come, catch the lucrative swordfish
and catch and kill more turtles."
Although U.S. fishermen must take yearly classes on
resuscitating federally protected endangered species such
as the leatherback, he said, "The foreign fleet
doesn't have a clue. Some of the turtles they catch would
live if we caught them."
Todd Steiner, director of the Turtle Island Restoration
Network, said the focus on the U.S. fleet is just the
first step toward a global swordfish long-lining ban.
"The United States needs to be a leader. We cannot
impose something on someone else, if we are not willing to
impose it on ourselves."
For now, scientists say it will do little to slow the
demise of the leatherbacks, because the U.S. long-liners
make up only about 6% of the worldwide fleet.
The toll from fishing is reflected on the protected beach
here, where tourists and researchers — not to mention
poachers — used to have a hard time navigating the beach
at night without stumbling over one of the table-sized
beasts digging holes. Now leatherbacks are an unusual
sight.
On a recent moonless night, the last female of the season
hauled her 700-pound bulk out of the ocean, hissing under
the strain of gravity.
Oblivious Mother
Driven by prehistoric instinct, she seemed oblivious to
the khaki-uniformed rangers who swarmed around her with
flashlights while she artfully scooped sand from the nest
with her back flippers. She paid no attention as they
checked her bar-coded ID tag and measured her leathery
shell at nearly 5 feet long and 3 1/2 feet wide.
Nor did she object when a guard, borrowing an old
poacher's trick, dug out an adjacent hole so he could
catch the racquetball-sized eggs in a plastic bag before
they ever hit the sand. The eggs were reburied at a more
secure location on the beach.
Besides overseeing this work, U.S. university researchers
Paladino and Spotila also run the nonprofit Leatherback
Trust, which aims to raise$10 million to help Costa Rica
buy beachfront land from foreign speculators so it can
expand the tiny park's boundaries.
Leatherbacks in the last dozen years have been driven from
the neighboring beach of Tamarindo by hotels and cabins
sprouting on the shore. Development alters the sand dunes
used by turtles for nesting, scientists say, and frightens
females away with bright lights.
Now they are trying to fend off a Best Western Hotel and a
186-house subdivision proposed for the remaining nesting
beach at Playa Grande.
"We can't let this nesting beach go, not on our
watch," Paladino said. "Not when you realize
that this is one of last places where you can see
dinosaurs come out of the ocean and walk on the
earth."
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