BOOKS: Witness to Extinction How We Failed to Save the Yangtse River Dolphin
From ANIMAL PEOPLE, December 2008:
Witness to Extinction
How We Failed to Save the Yangtse River Dolphin
by Samuel Turvey
Oxford University Press (198 Madison Ave., New York,
NY 10016), 2008.
224 pages, paperback. $29.95.
Samuel Turvey, born in Lohja, Finland, as a child enjoyed
a rare sighting of the Lake Saimaa seal. Landlocked by receding
glaciers about 9,500 years ago, the Saimaa seal has adapted to
living in fresh water. At the time, researchers believed there were
barely 100 left. The population rose to 280 in 2005, but has since
dropped to 260.
“Getting entangled in fishing nets is the biggest single
cause of death. If we get rid of that, the Saimaa seal could
probably survive global warming,” World Wildlife Fund representative
Jari Luukkonen recently told Terhi Kinnunen of Agence France-Press.
Turvey grew up to earn a Ph.D. in Chinese paleontology, but
inspired by his Saimaa seal encounter, felt impelled to try to
discover the fate of the baiji, the Yangtse river dolphin, last
known to exist when the last captive baiji died in 2002.
Turvey’s title, How We Failed to Save the Yangtse River
Dolphin, is a bit of a misnomer, since his involvement began after
the fact. Mentioned in ancient times, but apparently never as
abundant as the now scarce Yangtse River porpoise, the baiji was
probably already headed toward extinction when 17-year-old American
duck hunter Charles Hoy shot the first scientifically described
specimen in 1914.
Baiji were at times hunted for food and oil, especially
during the so-called Great Leap Forward under Mao tse Tung, when as
many as 30 million Chinese people starved to death, but mostly they
appear to have been accidental victims of “rolling hook” fishing,
fish netting, and boat traffic along the river which has long been
among China’s busiest thoroughfares.
Not more than 200 baiji were left by the time field studies
started circa 1979. Inept attempts to catch baiji for captive
breeding, lack of knowledge about the needs of baiji once captured,
institutional rivalries, and the perception of international
conservation organizations that the baiji was a lost cause all
contributed to the failure of last-ditch efforts to resuscitate the
species.
Turvey appears to be especially bitter about the lack of
grant funding allocated to saving the baiji, seemingly oblivious to
the need for someone to raise the funds to be granted. If major
funders would not try, baiji enthusiasts might have taken their case
directly to the public via direct mail and e-mail.
As Turvey notes, marine mammologist Stephen Leatherwood
became involved toward the end of his life, and knew how to do what
needed to be done, but died in January 1997. That probably doomed
the whole cause.
Turvey’s role was to organize and lead a two-boat survey of
the entire length of the Yangtse and major tributaries in 2005 that
found not a trace of a living baiji and no credible reports of recent
sightings. A blurred and distant video of a purported sighting in a
tributary turned up in 2006, but even if one or two baiji remain,
chances are slim that they will be enough to rebuild the population.
Turvey recounts the loss of the baiji in hopes that lessons
can be learned on behalf of other rare species, including the
vaquita whale, found only in the Gulf of California.
The North American Commission for Environmental Cooperation
reported in October 2008 that only about 150 vaquitas remain in the
wild, while as many as 40 are killed each year by fishing nets.
Other Asian river dolphins have declined to the scarcity that
the baiji reached before anyone sounded an alarm.
The Wildlife Conservation Society and Bangladesh Cetacean
Diversity Project told Shafiq Alam of Agence France-Presse in October
2008 that they have counted an unexpectedly large population of 5,832
Irrawaddy dolphins in the estuaries of coastal Bangla-desh. But that
is almost the only unequivocal recent good news about Irrawaddy
dolphins in any of their five Southeast Asian habitats.
Fewer than 100 Mekong Irrwaddy dolphins remain in northern
Cambodia, Sun Mao of the Cambodian Rural Development Team told Guy
Delauney of BBC News in July 2008. “A ban on the use of gill nets
has cut down the number of dolphins accidentally caught,” Delauney
reported. “Instead, CRDT has helped locals to reduce their reliance
on fishing by offering alternatives such as poultry farming.”
Even from a perspective limited to species conservation,
increased poultry farming in estuarial dolphin habitat would be
alarming. Poultry excretia, rich in phosphorus, is implicated in
declining water quality in U.S. inland waters from the Arkansas River
to Chesapeake Bay. River dolphins would be affected if the U.S. had
any.
Thirty years after Pakistan prohibited hunting the Indus
river dolphin, which is blind and lacks a dorsal fin, this species
had increased to 1,330, according to a spring 2006 survey. The
Indus river dolphin appeared to be a short-term beneficiary of a 25%
increase in glacial melt from the Himalayas, attributed to global
warming. As the glaciers recede, this stimulus will decline.
The dolphin population of the Upper Ganga river in India has
increased from 20 to 40 since 1993, World Wildlife Fund freshwater
program coordinator Sandeep Behera told The Hindu in November 2008.
Accomplishing this required building a sewage treatment plant,
stopping fishing and mining along 165 kilometres of river, and
persuading farmers to fertilize only with cow manure.
Supot Chandhrapornsil of the Thailand Department of Marine
and Coastal Resources warned in May 2008 that only about 40
Indo-Pacific humpback dolphins remain in Khanom Bay at Nakhon Si
Tham-marat. Four of the pink dolphins were killed by entanglement in
fishing nets during the first five months of 2008.