First conservation translocation project of the East Asian trixspermum on Jeju Island, South Korea

Summary

East Asian thrixspermum, an epiphytic orchid otherwise found across Japan, China and Korea, is known in Korea from a single site in the Donnaeko Valley on Jeju Island, where fewer than 50 individuals survive and over-collection for the ornamental trade remains an ongoing threat despite the habitat sitting inside a national park. Working from just one wild-collected fruit gathered by Halla Arboretum staff in 2011, the Korea National Arboretum began artificial propagation in 2012, and translocated 216 seedlings back into the wild. Annual monitoring tracked survival, flowering, fruiting and human interference over the following two years. Survival fell from 100 percent at planting to 73 percent after one year and 63 percent after two, but reproduction improved over the same period, with the share of flowering individuals rising from about 10 percent in the first year to 26 percent in the second, and no reports of human interference at the site. No seedlings had yet emerged naturally by the end of monitoring. Because every translocated plant descends from a single wild fruit, the new population is expected to have very low genetic diversity, and the epiphytic species is also slow to settle onto its host branches. The project rates itself partially successful, citing strong flowering and fruiting rates and an effective local monitoring partnership against the declining survival rate and the project's still-short track record.