korea is a peninsula located in northeast asia. ecologically, baekdu mountain alpine zone and two large rivers isolate the korean peninsula from the continent. the yalu river in the northwest of the korean peninsula and the tumen river in the northeast play a role in limiting the movement of wildlife from china and russia. therefore, the isolation by tuman and yalu rivers from the korean peninsula shows that the percentage of endemic species of freshwater fish and insects to be high. an endemic species refers to a species of organism that lives only in geographically limited areas or countries, and represents species that live only in that area all over the world. of the 100,000 species currently identified, approximately 10% are believed to be endemic species in korea. four species of mammals, four species of algae, five species of amphibians, one species of reptiles and 59 species are known as endemic species in korea.