Taipei:The endangered Formosan landlocked salmon has made a successful return to the upper reaches of Sijielan Creek in central Taiwan. A recent survey conducted by the Shei-Pa National Park Headquarters recorded 117 adult salmon following an aerial release last year.
According to Focus Taiwan, the survey indicated a visible survival rate of nearly 50 percent and documented courtship and pairing behaviors among the fish. This suggests that the salmon are likely to spawn naturally in the wild as early as November. The salmon, now nearly two years old, have matured into healthy adults, with distinct secondary sexual characteristics observed in both males and females.
Sijielan Creek is described as the final piece in restoring the species across its historic habitat within the Dajia River basin. While the salmon had already been successfully restored in other creeks such as Qijiawan, Hehuan, Nanhu, and Luoyewei, previous reintroduction efforts in Sijielan Creek faced challenges due to habitat degradation.
Atayal traditional knowledge notes that Sijielan Creek once supported a thriving wild population of the salmon, which later vanished due to environmental changes and human development. A decade ago, the habitat began to recover naturally when floodwaters destroyed a downstream check dam, allowing natural erosion to recreate the deep pools and gravel beds essential for the salmon's survival.
In September 2025, the headquarters utilized a helicopter for the first time to airlift 240 young salmon to the creek. A research team recently trekked from Huanshan Village, covering a 3.1-kilometer trail and a 5.5-kilometer river section, to assess the outcome. They recorded the salmon in a 600-meter section around the release site, noting an observed survival rate of 48.75 percent. Salmon were also seen beyond the surveyed area, suggesting a possible survival rate exceeding 50 percent.
The headquarters plans to continue monitoring the emergence of juvenile salmon and the population's resilience to flooding, with comprehensive survey results expected by year-end.
