Larval Fish Validation Pilot-Test Methods for Live Dead Determination

Under the pending 316(b) rules, affected facilities are required to characterize entrainment with an understanding of entrainment mortality. To effectively assess entrainment mortality, facility managers, scientists and permitting authorities will need to agree on entrainable organism condition descriptions (e.g., live, dead, moribund) that are applicable and acceptable for entrainment mortality calculations. This project tested two methods that may offer scientists efficient and effective approaches for live/dead determinations of larval fish and egg samples in the field. Neutral Red dye and electrical stimulation tool methods were developed and tested on entrainable organism samples. The results found that each method offered pros and cons regarding effectiveness for characterizing live verses dead organisms in the laboratory. The protocols where then tested in a pilot field application for effectiveness and efficiency as a field technique. Results of the pilot-level lab and field applications will be presented to describe their potential value in entrainment sample characterization.