Application of Life Cycle Risk Assessment (LCRA) of Fish to Different Suburban Streams

A Life Cycle Risk Assessment (LCRA) proposed in our former study was applied to 12 suburban streams to evaluate crucial stress and habitat conditions for 15 freshwater fishes in Japan. In LCRA, 8 stresses produced by human activities were taken into consideration, referring to the literature. Field survey and literature reviews were conducted to identify the present existence and distributions of corresponding fishes in the streams which have different pollution levels and morphologies. Crucial stresses frequently identified by the LCRA were depletion of dissolved oxygen (DO), disappearances of habitats (e.g. deep and shallow), disappearance of spawning area due to benthic deposition, and existence of obstructions in the streams. Most LCRA results regarding existence or non-existence of 15 fishes were in fairly good agreement with field survey or literature reviews results. From these results, we thought the present LCRA would be a useful tool in assessing crucial stress as well as in evaluating habitat conditions in steams, which could be used for the restoration of steams.