Assessing Salmon Condition: Where to Go from Here?

Juvenile salmonids encounter many natural (e.g., parasites, diseases) and anthropogenic-related (e.g., diversions, dredging, sound, turbine) stressors. Monitoring behavior (e.g., movement) and physiological regulation (e.g., stress, immune, endocrine) as indicators of fish condition are crucial for the early detection of juvenile salmonid condition. It is not feasible, though, to evaluate all behavioral and physiological responses. Consequently, it is vital to identify a suite of responses that are indicative of the juvenile salmonids overall condition and/or health state at different juvenile stages and in relation, when possible, to location within the watershed. In addition, because of the various biological levels involved, resultant data are not often further developed into actionable information for managers, researchers, and agencies. This presentation provides the results of a metadata analysis for evaluating the physiological condition of juvenile salmonids moving through hydropower systems. The analysis includes 142 peer-review publications in which most common condition and stress measures are ranked by efficacy of approach in relation to life stage (fry, parr, smolt) and watershed (lake, upper and lower river, estuary). The presentation identifies information gaps (e.g., no baseline data or run), and suggestions for needed assessments for evaluating juvenile salmon condition in the future.