2019 RED BLUFF DIVERSION DAM ROTARY TRAP JUVENILE ANADROMOUS FISH ABUNDANCE ESTIMATES

Brood year (BY) 2019 juvenile winter Chinook salmon (Oncorhynchus tshawytscha) estimated passage at Red Bluff Diversion Dam (RBDD) was 3,813,589 for fry and pre-smolt/smolts combined. The fry-equivalent rotary trap juvenile production index (JPI) was estimated at 4,691,7645 with the lower and upper 90% confidence intervals (CI) extending from 2,630,095 to 6,753,433 juveniles, respectively. The estimated egg-to-fry (ETF) survival rate, based on the BY2019 winter Chinook fry-equivalent JPI was 17.5%, below the 21-year average ETF survival rate of 24.0%. The range of ETF survival rates based on the 90% CI was 9.8% to 25.2%.