Formosan Landlocked Salmon

The Formosan landlocked salmon (Oncorhynchus masou formosanus) is the world's southernmost salmonid population — a glacial relic stranded in Taiwan's mountains at the end of the last ice age, surviving today in just 5 kilometres of viable stream habitat within Shei-Pa National Park. Conservation investment has delivered dramatic results: the population fell to approximately 200 individuals after Typhoon Herb in 1998, then recovered to over 3,000 fish by 2023 through a NT$200 million habitat restoration programme. Survival depends on the Cijiawan River remaining below 17°C year-round — a thermal ceiling nearly 10°C stricter than the upper heat tolerance of other Oncorhynchus masou subspecies in Japan and Korea, making this population acutely sensitive to climate warming. Wuling Farm's purpose-built viewing platforms allow close observation without entering the stream channel. The most productive viewing months are October through February, when fish are most active near the surface. The recovery rate of 1,400% since 1998 outperforms the Purple Crow Butterfly's stable roosting populations, though the salmon's viewing season is 4 months shorter than the butterfly's November-to-March window.