earticle

영어

In recent years, natural populations of indigenous freshwater species have drastically decreased worldwide, predominantly due to anthropogenic pressure, such as habitat destruction, introduction of exotic species, and potentially climate change. Consequently, a number of species are now under threat of extinction. To recover endangered or vulnerable populations, conservation and restoration management efforts through stocking (e.g. assisted migration) or translocation are currently under way in many parts of the world, including Korea. In this study, we evaluated the current population status of three Korean endangered freshwater fish species (the Manchurian trout Brachymystax lenok tsinlingensis and the sculpins Cottus hangiongensis and Cottus koreanus) that play important ecological roles in their respective ecosystems. We found that extents of within-population genetic diversity were generally low in all three species examined, suggesting that their effective population sizes (Ne) have been typically small. South Korean populations of these species were all substantially genetically isolated from one another (except C. hangiongensis with an amphidromous life style), indicating that limited ongoing gene flow has been taking place among populations. We suggest that stocking or translocation for these ecologically important but endangered Korean populations should be undertaken carefully, considering not only genetic diversity of source/recipient populations, but also the ‘natural’ population structure that is possibly related to local adaptation to their particular environments. Further, the genetically unique populations or groups (e.g. National Park populations) of our study species should be managed as distinct conservation or “evolutionarily significant units (ESU)” in the future.