Fisheries, Subsistence, and Habitat
Publications Searchable Database
Search Again| Division: | Sport Fish |
| Title: | Estimates of Chinook salmon abundance in the Kenai River using split-beam sonar, 2004 |
| Author: | Miller, J. D., D. L. Burwen, and S. J. Fleischman |
| Year: | 2007 |
| Report ID: | Alaska Department of Fish and Game, Fishery Data Series No. 07-57, Anchorage |
| Abstract: | Chinook salmon Oncorhynchus tshawytscha abundance in the Kenai River in 2004 was estimated using side-looking split-beam sonar technology. Early (16 May-30 June) and late (1 July-10 August) runs of Kenai River Chinook salmon have been monitored acoustically since 1987. A 200 kHz split-beam sonar system has been used since 1995 to estimate numbers of adult Chinook salmon migrating into the Kenai River. From 1987 to 1994, a 420 kHz dual-beam sonar was used to generate similar estimates. In 2004, the sonar project operated 16 May through 5 August. The total estimated upstream Chinook salmon passage in 2004 was 67,873 (SE = 641) fish: 15,498 (SE = 261) fish during the early run and 52,375 (SE = 585) fish during the late run. Total late-run passage estimate extrapolated through 10 August was 56,205 (SE = 1,784) fish. The standard errors associated with these estimates reflect only sampling error and not other sources of uncertainty including target detection, species composition, direction of travel, and target tracking. The early-run peak daily passage occurred on 10 June, with 50% of the run having passed by 14 June. The late-run peak daily passage occurred on 16 July, with 50% of the late run having passed by 18 July. |
| Keywords: | split-beam sonar, dual-beam sonar, Chinook salmon, Oncorhynchus tshawytscha, acoustic assessment, Kenai River, riverine sonar, early run, late run. |