Abstract
We examined effects of fine sediment on embryo survival rate and on redd environments of an endangered species, Sakhalin taimen (Hucho perryi). Sediment accumulation, permeability, water quality and embryo survival were quantified at the redds in mountain streams in northern Hokkaido, Japan, and their correlations were assessed. The results indicated that the survival rate was negatively correlated with dissolved oxygen concentration. However, the direct effects of fine sediment on the embryo were not clarified because the accumulations were low in those streams. Moreover, results clarified that accumulations lower the interchange ability of redd water and conduction of heat, despite the low accumulation level. Further research must investigate the fine sediment effects associated with heat flux.
