Guidance for Site-Specifically Assessing the Health of Fish Populations with Emphasis on Canada's Environmental Effects Monitoring Program

Abstract Techniques have been developed over the past two decades to site-specifically assess effects of contaminants on the health of fish populations using a sentinel species approach. National environment effects monitoring (EEM) programs have been implemented in Canada for pulp and paper effluents since 1992 and liquid metal mining effluents since 2002 to monitor effects of these discharges on the health of fish populations. The major criticisms of past EEM fish population surveys can be separated into concerns about the adequacy of the reference sites, the potential impacts of confounding factors, the ecological relevance of endpoints used, the influences of natural variability, concerns over statistical design issues, and potential genetic influences on species characteristics. This paper provides input to deal with these issues and guidance on the selection of sentinel species, timing of sampling, and nonlethal sampling methods to evaluate the health of fish populations. Sample size requirements, effect sizes, and power analysis are also discussed as well as data analysis guidance needed to obtain reliable results.