최상위 포식자인 외래종 큰입배스가 호수생태계 건강성에 미치는 영향

This study was carried out to analyze the difference of fish fauna, ecological indictor characteristics, biological status of other fish population and fish community structures between two groups of reservoir ecosystems along with invasion of introduced alien species, largemouth bass (Micropterus salmoides), top carnivore in the lentic ecosystem. Six reservoirs (YdR, GcR, MsR, BgR, GpR, and YgR) were selected and divided as two groups; reservoirs non-invaded and invaded by M. salmoides were RNIv and RIv respectively. Total 28 species 11,519 individuals were sampled in RNIv whereas 19 species 1,925 individuals were sampled in RIv. While Korean endemic fish population dominates in RNIv, exotic fish species, especially M. salmoides population dominate in RIv. In the mean time, sensitive species and water-column species dominates in RNIv, while tolerant species and carnivore species dominate in RIv. The analysis of total-length size distribution showed some difference, particularly in special size group between RNIv and RIv. Also, the analysis of total fish biomass showed significant difference in accordance with largemouth inhabitation. According to the fish community analysis results, as M. salmoides proportion increased, species richness and diversity were decreased. Overall data suggests that the dominant distribution of largemouth bass may influence simplification of the fish fauna, species composition as well as community structure and affect the length distribution and biomass of other fish population negatively.