Dolphin species' extinction helps cousin's survival

Updated: 2013-12-22 07:43

(China Daily)

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While Anhui province's Tongling River Dolphin National Nature Reserve was created in the 1980s to save the now functionally extinct white-flag dolphin, it has been reincarnated as a refuge for China's finless river porpoise subspecies.

The reserve was founded in 1985 to survey and protect the dolphin. But none of the creatures have been seen anywhere since. The species was declared functionally extinct in 2006.

But since 2001, the center has tried to make use of an earlier start to protect the critically endangered Chinese porpoise subspecies N. p. asiaorientalis, fewer than 1,000 of which survive in the Yangtze River and two lakes. The subspecies' colloquial name, "river pig", hails from how commonplace the creatures were decades ago.

The reserve's first four porpoises came after nearby fishermen accidentally caught them. The center now contains 10 of the rare river mammals - half of which were captured, half of which were bred in captivity.

Chief engineer Jiang Wenhua recalls he had to work as both engineer and breeder because the reserve was short-staffed when he arrived in 1992.

That was when he says he learned how to care for the creatures - and do so lovingly.

Jiang feeds the animals 10 kilograms of minnows four times a day.

"River porpoises are picky eaters," he says. "Their esophagi aren't wide enough to take fish longer than 7 cm."

Feeding begins at 10 am, when Jiang thwacks the water with a stick, as if striking a dinner bell. The minnows come from nearby villages' fishermen. The protection zone spans two islands, and Tieban and Heyue villages.

But the same locals who provide the porpoises' food also pollute their water, Jiang says. From the center's observation ward, villagers can be seen washing their clothes in the river.

"Of course, that affects the water for the porpoises, including the more than 30 outside the protection zone," Jiang says. "The dilemma is villagers can't afford to use water at their homes. There aren't specific rules about what they can and can't do. So, all we can do is try to persuade them."

In recent years, university students have begun spending their vacations educating the villagers.

Jiang says working with the "river pigs" reminds him and his colleagues of their childhoods. Jiang was born in Tongling and grew up near the river.

"There were so many river pigs then," he recalls. "You could see them jumping out of the water. People never thought of fishing for them for any reason, let alone food.

"It's fun to feed them. Locals used to toss them minnows all the time. They seem to smile when they jump to catch the fish you throw. But that once-everyday sight might disappear forever."

Jiang believes the river porpoise might become extinct for the same reasons the dolphin did.

The Yangtze River, known as China's "golden waterway", serves as a major transportation artery for the booming riverside economies.

This means the porpoises - like the dolphins before them - suffer from traffic, pollution and food depletion, as fish become scarcer.

Tieban native Fang Changsheng, who lives near the reserve, has seen the decline of both river porpoises and fish. "The porpoises were everywhere when I was a kid," he recalls.

"But I haven't seen them for years."

Extreme weather is another killer. Jiang recalls one porpoise froze to death in the 2008 blizzard.

"Their situation to some extent is indicative of the entire environment we all live in," Jiang says.

- Kang Bing and Zhang Yue

(China Daily 12/22/2013 page3)