Sonar Estimation of Salmon Passage in the Yukon River Near Pilot Station, 2019
Author: Ryan P. Morrill
Publisher:
Published: 2021
Total Pages: 71
ISBN-13:
DOWNLOAD EBOOKThe Pilot Station sonar project has provided daily passage estimates of Chinook (Oncorhynchus tshawytscha), chum (O. keta), and coho (O. kisutch) salmon for most years since 1986. Fish passage estimates for each species were generated in 2019 using a 2-component process: (1) estimation of total fish passage with 120 kHz split-beam sonar and an adaptive resolution imaging sonar, and (2) apportionment to species by sampling using a suite of gillnets of various mesh sizes. An estimated 3,161,920 fish passed through the sonar sampling area between June 2 and August 31. Of those fish, 690,494 passed along the right bank, and 2,471,426 passed along the left bank. Included, with 90% confidence intervals, were 172,242 ± 18,964 large Chinook salmon (>655 mm to fork of tail), 47,382 ± 7,725 small Chinook salmon (≤655 mm to fork of tail), 1,402,925 ± 85,902 summer chum salmon, 842,041 ± 37,151 fall chum salmon, 86,401 ± 9,530 coho salmon, 42,353 ± 8,893 pink salmon, 270,434 ± 36,596 cisco, 196,905 ± 30,456 humpback whitefish, 25,694 ± 5,256 broad whitefish, 22,673 ± 5,948 sheefish, and 52,870 ± 5,659 other species.