By
Brent Crane,
December 24, 2018, The New Yorker
A
few months ago, on a sunny afternoon in northern Vietnam, I set off in a small
fishing boat outfitted with a motorbike engine to find the world’s most
endangered turtle. Of the planet’s four known remaining Yangtze giant
softshells (Rafetus swinhoei), only two reside in the wild. Both occupy
separate lakes in northern Vietnam. The other two, the world’s sole surviving
couple, live in a zoo in southern China; for years, scientists have been trying
to breed them, unsuccessfully. (The male has a damaged penis.) The two wild
turtles represent the final hope for the species. I had boarded the boat hoping
to glimpse one of them in Dong Mo, a fourteen-hundred-hectare lake an hour or
so west of Hanoi. I was joined by a group of Vietnamese conservationists allied
with the Asian Turtle Program
(A.T.P.) of Indo-Myanmar Conservation, a U.K.-registered nonprofit
organization. The odds were against us.
The
Yangtze giant softshell occupies a regal position in national lore. Legend has
it that, in the fifteenth century, in a Hanoi lake called Hoan Kiem, the turtle
was the keeper of a mythic sword used to liberate the country from Chinese invaders.
Sightings are said to bring good fortune. In 2016, when Hoan Kiem’s sole
softshell—which was nicknamed Cu Rua, or “great-grandfather turtle” in
Vietnamese—was found dead, it made international
news. (Politically, it was bad timing: some joked that its death, which came on
the eve of an important gathering of the Vietnamese Communist Party, signalled
the regime’s demise.) The country mourned. “It was like losing part of our culture,”
Hoang Van Ha, an A.T.P. conservationist, told me.
The
turtle in Dong Mo is estimated to be forty or fifty years old, which is
considered quite young. For the past eleven years, A.T.P. volunteers have been
doing near-daily patrols on the lake, keeping an eye on the turtle and
observing its behavioral patterns. The species lives up to its name, with
individuals growing to more than three hundred and sixty pounds. Though it used
to be common in the region, a combination of hunting, environmental degradation,
and rampant development has brought it to the existential brink. Dong Mo’s
patrollers usually witness the reptile only once every few weeks, Ha told me,
but observers had seen it surface several times in the hours before I arrived.
It was the first clear day in weeks, and the turtle was basking.
Dong
Mo is a soupy-brown color, and the lake is filled with bamboo-choked isles. It
was formed in the seventies, when a dam was built on the Red River, the major
waterway of northern Vietnam. Scientists think that the Dong Mo turtle was
trapped there after the river’s damming.
(Historically,
the turtle has lived in large rivers and channels.)
Conservation-wise,
this was a blessing. “If this animal were out in the Red River, there would be
nothing we could do to monitor it or give it protection,” Tim McCormack, an
A.T.P. program coördinator, told me. In 2008, heavy rains caused the dam to
overflow. The turtle escaped, but only into a fisherman’s net. It took six
hours of negotiation between N.G.O. volunteers, the police, local cadres, and
the fisherman to rescue the animal. In 2013, conservationists successfully
lobbied for a law that fully protects the turtle from capture or sale.
Since
then, other safeguards have been installed. On Dong Mo, the A.T.P.
conservationists showed me a mesh net, sixty-five feet deep, that was laid
across a portion of the lake to prevent escapes. I asked if they ever worried
that the turtle would become entangled. “Normally, when he encounters the net,
it just swims away,” Ha said. The conservationists lifted the net out of the
water and tossed caught branches to the side. Nguyen Tai Thang, a
conservationist wearing a pith helmet, repaired a hole with some rope. The
turtle was nowhere in sight.
Though
the giant softshell’s future appears grim, there have been a few inspiring
developments of late. In April,
the existence of the second wild specimen was confirmed in a lake called Xuan
Khanh. The discovery was made using a new method known as environmental DNA, or
eDNA, which reveals the presence of animals by genetically analyzing water
samples. eDNA could be used to confirm other softshell specimens across Asia.
Genetics
are also coming in handy elsewhere. Last year, a paper published in Scientific
Reports showed that, contrary to prior understanding, softshell turtles possess
sex chromosomes, which means that they can be sexed using DNA analysis. Minh
Le, an evolutionary biologist at Vietnam National University and a research
associate at the American Museum of Natural History, told me that preparations
were already being made for a test on the Dong Mo turtle. (DNA samples were
procured during its escape and capture in 2008.) Assuming things go smoothly,
they should have results early next year.
The
sex of the two Vietnamese turtles will determine the next course of action. If
both are male, plans may be made to transfer either a whole turtle or semen
samples to the Suzhou Zoo, in southern China, where the only known female
lives. In July, the Suzhou Zoo made a formal appeal to the Vietnamese government
to do just this, but no decision has been made. Since 2008, the zoo has been
trying to get its pair to produce offspring, but the male’s member, mutilated
in a battle with another male some decades ago, produces shoddy sperm. (The
other male died in the fight.) It is also very old, likely over a century,
Gerald Kuchling, an Austrian turtle biologist who has overseen the Chinese
breeding program since the early two-thousands, said.
Artificial
insemination has been attempted three times on the Suzhou pair, but no eggs
have hatched. If conservationists can change that, population numbers could
rebound rapidly. “It only takes a couple of years of breeding success and there
could be hundreds of individuals,” McCormack told me. But even hatchlings
present new problems: when the population comes from the same family,
inbreeding becomes an issue. Moreover, all of the structural problems that
decimated the turtles in the first place persist. Dams continue to be built
along southeast Asian rivers, wetlands are being developed, and demand for
turtle meat still tempts hunters.
Perhaps
Dong Mo can serve as an example of local conservation success. Through
negotiation with land managers, the A.T.P. was able to create a no-fishing zone
within two portions of the lake, giving the turtle its own hunting grounds. The
organization has also educated local communities about the turtle.
Conservationists give lectures at schools, hang up flyers in villages, and even
host the Turtle Football Cup, an annual soccer tournament on the banks of Dong
Mo. Winners get a large poster of the turtle.
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