이석 분석에 의한 연어의 서식환경과 계군 구분

Abstract

Since Reibisch's observations in 1899, otoliths have been used to identify the age and daily rings of fish. However, the relatively sudden development of otolith elemental analyses appeared in the 1980s. The advent of otolith chemistry expanded and applications of otoliths to environmental recorders. Elemental composition analyses called elemental tags or fingerprints, of the fish otoliths have been applied to study age, growth, stock identification, temperature and salinity histories, migration pathways, anadromy, pollution of habitat, and chemical mass marking. To investigate the stock identification and habitate characteristics of chum salmon (Oncorhynchus keta) in the North Pacific Ocean, the stable isotopes O, C and trace elements in otoliths were measured. Otoliths were collected from four sites 9canada, Japan, Korea and Usa) during 1997-1999 spawning seasons except japanese salmon inn1999. The values of the two isotopes of adult salmon separated largely into two groups: Asian and North American chum salmon. From the trace element analysis, we suggest that chum salmon might move onshore/offshore or north/south during its growing stage. The result of discriminant analysis with 23 elements represents distinct separation in accordance with natal areas of stocks. Therefore, otolith chemistry is a very effective technique for stock separation and for revealing the effects of environment of salmon populations.