Sunday, August 4, 2013

Balancing on the brink (Taiwan Review)

It is a normal weekday at Wuling Recreation Area, which is under the jurisdiction of Shei-Pa National Park and lies deep in a mountainous part of central Taiwan’s Taichung City. Tourists are trickling through the park’s Taiwan Salmon Eco Center, a building named for and housing a small number of Formosan landlocked salmon [shown below left], members of an endangered fish species found nowhere else on Earth. “I didn’t know it was the fish on the money,” says one visitor, pointing to the image of two salmon on a replica of Taiwan’s NT$2,000 (US$67) banknote. Other sightseers comment on the salmon’s diet (mostly aquatic insects), or how healthy the fish look.

For most people, the center is the only place where they can get near enough to a school of Formosan landlocked salmon to see the spots that mottle the top and lower parts of each fish’s body. To protect the salmon, tourists are not allowed close to Qijiawan Creek [lower right], the nearby waterway that is the species’ main habitat. The creek, which is 15.3 kilometers long and 7 to 12 meters wide, drains an area of 76 square kilometers.

“The center provides a chance for the public to see these beautiful fish up close. When they can see the salmon, they’ll appreciate and recognize the need to protect them. Then, they’ll give their support to conservation measures,” says Lin Hsing-juh, a professor in the Department of Life Sciences at National Chung Hsing University in Taichung and leader of the Wuling Long-Term Ecological Research (WLTER) team. He explains that the salmon displayed in the center were not taken from Qijiawan Creek, but rather bred in captivity.

Official efforts to bolster the Formosan landlocked salmon population date from the 1980s, when the species was listed first as a valuable natural asset under the Cultural Heritage Preservation Act, then as a protected species under the Wildlife Conservation Act. Scientists, however, have been taking an interest in the fish for almost a century.

Taiwan was a Japanese colony from 1895 to 1945. In 1917, while visiting a police station in what is now Yilan County’s Datong Township, an assistant to Japanese scientist Masamitsu Oshima (1884–1965) was told that fish similar to Japanese trout existed in high-altitude streams in Taiwan’s northeast. With the help of Atayal aborigines in the Yilan area—who called the species bunban or kulubang—the assistant obtained a salted tail of one fish.
When Oshima returned to Taiwan from Stanford University in the United States early the following year, he was intrigued. He gathered additional specimens and set to work describing the fish’s characteristics in words and diagrams. In a June 1919 Japanese-language article in an agricultural bulletin, Oshima alerted the world to the existence of what is today commonly called the Formosan landlocked salmon.

In his initial report that year, Oshima dubbed the species Salmo saramao, Saramao being the name of an Atayal community near today’s Lishan Village in Taichung City’s Heping District from which a specimen was taken. But when David S. Jordan, a former Stanford president who served as Oshima’s research instructor, wrote the first English-language report about the discovery, he decided Oncorhynchus masou formosanus was a more suitable label, reasoning that Formosa (as Westerners then called Taiwan) was known to the outside world, whereas Saramao was not.

Originally regarded as a subspecies of the cherry salmon (aka masu salmon, Oncorhynchus masou) found in Japan, the Korean Peninsula and Russia’s Far East, the Formosan landlocked salmon is now regarded by most researchers as a species in its own right. Accordingly, its scientific name has been amended to Oncorhynchus formosanus, under which the species is listed in the Fish Database of Taiwan maintained by Academia Sinica, Taiwan’s foremost research institution, as well as in the International Union for Conservation of Nature Red List of Threatened Species.

Scientists agree that Taiwan’s salmon shares ancestry with its Japanese counterpart, and that DNA comparisons suggest the two species split around 800,000 years ago. In a paper published by the Journal of the National Taiwan Museum in 2010, Shieh Ying-tzung, a member of the museum’s Department of Research, theorizes that “the most likely timing of ... salmon straying and moving onto Taiwan is 0.78 million years ago after a meteorite strike.” The impact, he says, not only led to significant global cooling but also caused magnetic north and south to switch places. “This combination of cooler sea temperatures and the salmon’s potentially confused magnetic tracking sensitivity would have allowed northern cherry salmon populations to stray southward as far as Taiwan..."

To read the rest of this article, which appears in the August issue of Taiwan Review, click here.

No comments: