| Summary: | Thesis (M.S.) University of Alaska Fairbanks, 1989 The effects of delays on the spawning run of Arctic grayling in Fish Creek, a tributary of the Jack River, near Cantwell, Alaska were examined. Tagged grayling were delayed for 3, 6, or 12 days, and then released; control fish were released within 12 hours of capture. During the delays, a high proportion of females became ripe; most males were ripe before the delays and remained ripe over a longer period than females. Delayed and control fish were monitored by the recapture of tagged fish in upstream traps. Females released in a "running-ripe" condition migrated at higher rates, but failed to reach upstream areas in similar proportions as those of "less ripe" females. Reduction in distances traveled by grayling as a result of longer delays may lead to the use of non-preferred spawning habitats, underuse of spawning areas upstream, and decreases in recruitment. I recommend that spawning delays for Arctic grayling not exceed 3 days. Alaska Department of Transportation and Public Facilities, and Federal Highways Administration
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