Straits Times : Rare Taiwan fish in peril after forest fire

MAY 19, 2002

Rare Taiwan fish in peril after forest fire

Their numbers are down to fewer than 400, and they are threatened further by the pollution of the streams they inhabit

TAIPEI - Taiwan's Formosan landlocked salmon, one of the rarest fish in the world, is on the verge of extinction following a catastrophic week-long forest fire that threatens to pollute its habitat.

The salmon was once found in huge numbers in the rivers of the central mountain range of Taiwan 80 years ago when the island was still a Japanese colony.

At that time, it was a protected species and it was illegal to catch the fish.

But after Taiwan was returned to China at the end of World War II, the number of salmon decreased dramatically due mainly to over-fishing and the deterioration of their natural habitat.

Documents kept by the Council of Agriculture revealed that the 'National Treasure Fish' has disappeared from Tachia, Hohuan, Nanhu, Shihchiehlan and Yusheng streams in the past two decades.

'They can still be found in Chichiawan Stream and the lower part of Hsuehshan Stream,' the council document said.

In 1992, the agriculture authorities declared the two streams as part of the protective zone of Shei Pa National Park and conducted extensive preservation programmes to save the fish from extinction. In 1997, the government finally set up a special sanctuary for the salmon and the surrounding wildlife.

Still, the number of the landlocked salmon has never exceeded 1,000.

Last October, the park administration discovered that the number of salmon in the streams had fallen to fewer than 400, prompting the authorities to set up an artificial salmon culture ground.

'We have raised some 1,000 baby salmon and many have grown to 5 cm long. We will find new habitats for them and will not place them all in Chichiawan and Hsuehshan streams,' said park director Lin Yung-fa.

He said the recent forest fire in Lishan where the park is located would not pose any harm to the existing salmon in Chichiawan Stream.

But ecologists disagreed.

'Although the ash has not directly gone to the river, the acidic substance of the ash will dissolve in the soil and be carried to the river by rain water. This will pollute the river and threaten the salmon,' said a park ecologist who declined to be named.

The Lishan fire, the worst in a decade, destroyed 127 ha of forest land before being finally put out on Thursday.

Stringent conditions for spawning

The salmon, known by its scientific name Oncorhynchus masou formosanus, became a landlocked species after a violent earth-crust movement towards the end of the Ice Age millions of years ago.
It must spawn in clear-water streams at a temperature of no more than 16 deg C.
It was declared an endangered species in 1989 by Taiwan's agricultural authorities.
In 1997, the government finally set up a special sanctuary for the salmon and the wildlife around its habitat.