Author: Nicholas James Smith
Publisher:
ISBN:
Category : Animal radio tracking
Languages : en
Pages : 38
Book Description
A 2-sample mark-recapture experiment was conducted to estimate the abundance and upriver migration characteristics of adult Chinook salmon Oncorhynchus tshawytscha returning to the Kuskokwim River in 2016. Tagging occurred downriver from all known spawning tributaries, except the Eek River. A total of 621 Chinook salmon were marked with radio and spaghetti tags, of which 527 continued upriver migration and were used to estimate abundance. Radiotagged fish were tracked throughout the study area using a network of telemetry stations and a series of aerial telemetry surveys. Upriver escapement monitoring weirs served as 7 recapture locations, representing lower, middle, and upper river tributaries. A total of 21,590 Chinook salmon were evaluated for tags, and total tag recoveries was estimated at 94. Inriver abundance of Chinook salmon upstream of rkm 67 was 120,000 fish (95% CI: 99,304-147,502). Radiotagged Chinook salmon traveling to upriver tributaries were captured and tagged earlier in the run compared to tagged fish migrating to middle river tributaries. Chinook salmon returning to lower river tributaries were captured and tagged throughout the entire run. Chinook salmon swam at a median speed of 36 rkm/day (range: 31-41 rkm/day) through all portions of the mainstem Kuskokwim River upstream from Bethel.