Run timing and morphology of steelhead kelts from the Situk River

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1 Run timing and morphology of steelhead kelts from the Situk River Brian Marston Alaska Department of Fish and Game Division of Sport Fisheries Yakutat, Alaska

2 1995 to 213 Weir Counts of Kelt Steelhead from the Situk River Abundance Angler catch data Run timing and Temperature Samples Kelt Size Trends Color/Condition trends Wounding trends

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5 Temperature Celsius Situk River Thermograph from 9 Mile Bridge /1 1/26 2/2 3/17 4/11 5/6 5/31 6/25 7/2 8/14 9/8 1/3 1/28 11/22 12/17 Date

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10 Number of Steelhead Kelts 16, Kelt Count 1 Year Mean All Year Median 14, 12, 1, 8, 6, 4, 2,

11 Number of Steelhead Kelts 18, Yearly Steelhead Kelt Count (bars) and Sport Catch (line) from Situk River Weir; , 14, 12, 1, 8, 6, 4, 2,

12 Number of Steelhead Kelts y =.666x R² = , 1, 15, 2, Angler Catch

13 3/1 3/15 3/29 4/12 4/26 5/1 5/24 6/7 6/21 7/5 7/19 8/2 CFS and # of Steelhead Kelts Temperature in Celsius Average Kelt Emigration Timing for Situk River Mean CFS Mean # Steelhead kelts Mean daily temperature at bridge Mean daily weir temperature Date

14 Daily Count of Steelhead Kelts Daily Average Water Temperature Steelhead Kelt Count from Situk River Weir; Kelt count Temperature Celsius 4 2 7/15/23 7/8/23 7/1/23 6/24/23 6/17/23 6/1/23 6/3/23 5/27/23 5/2/23 5/13/23 5/6/23 4/29/23

15 Daily Count of Steelhead Kelts Daily Average Water Temperature Steelhead Kelt Count from Situk River Weir; Kelt Count Temperature Celsius /29/211 7/22/211 7/15/211 7/8/211 7/1/211 6/24/211 6/17/211 6/1/211 6/3/211 5/27/211 5/2/211 5/13/211 5/6/211 4/29/211

16 Daily Count of Steelhead Kelts Daily Average Water Temperature Steelhead Kelt Count from Situk River Weir; 26 Kelt Count Temperature Celsius /27/26 7/2/26 7/13/26 7/6/26 6/29/26 6/22/26 6/15/26 6/8/26 6/1/26 5/25/26 5/18/26 5/11/26 Date

17 Daily Count of Steelhead Kelts Daily Average Water Temperature in Celsius Kelt Count Steelhead Kelt Count from Situk River Weir; Temperature Celcius /29/212 7/22/212 7/15/212 7/8/212 7/1/212 6/24/212 6/17/212 6/1/212 6/3/212 5/27/212 5/2/212 5/13/212 5/6/212 4/29/212

18 Yearly Kelt Count Temperature Celsius May to June Yearly Average Temperature and Yearly Kelt Count from The Situk River; , 14, 12, 1, 8, 6, 4, 2, Kelt Count (lagged one year) May-June Temperature

19 Number of Steelhead Kelts y = x R² = Average May-June Temperature (lag one year)

20 SAMPLING

21 SAMPLING GOALS Sample 3-5 % across run based on target of 223 fish Tue and Thurs Tues early ; Thursday late Use previous 2 days count to anticipate sample size Data obtained Length Sex Wounding codes Color/condition codes. 1-3 Saprolegnia.yes or no PIT tag

22 Steelhead Kelt Total Length (mm) 9 Average total length (mm) of steelhead from the Situk River Female Male

23 Steelhead Kelt Total Length Group (mm) Length Distributions Per Year For Female Kelt Steelhead Sampled From The Situk River; ,15 1,1 1,5 1,

24 Steelhead Kelt Total Length Group (mm) Length Distributions Per Year For Male Kelt Steelhead Sampled From The Situk River;

25 Color 1 Color 2 Color 3

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27 Yearly Proportions Per Color/Condition Class In Samples of Female Kelt Steelhead from the Situk River Yearly Proportions Per Color/Condition Class In Samples of Male Kelt Steelhead from the Situk River

28 Percent of Kelts With Wounds 1 Percent of Kelts With Saprolegnia per sex from The Situk River; Female Male

29 Percent of Sampled Kelts with Wounds Percent of Fish With Wounds per sex from The Situk River; Female Male

30 Cumulative Number of Tags at Liberty Cumulative Recaptures and Percent of Tags Recaptured PIT Tagging Statistics from Situk River Steelhead Kelts; Cumulative Tags at Liberty Cumulative Recaptures % Recaptures Recapture Year

31 Summary Temperatures were associated with emigration timing Temperatures were associated with kelt numbers Kelt size differences per sex were not consistent among years Kelt abundance was negatively associated with kelt size Male kelt size distributions were more variable among years More male fish fell within trophy fish class (> 36 inches) No association of kelt abundance with angler catch PIT tagged fish return rate of 1% More males had Saprolegnia Males were classed lower in color condition No significant difference in male vs female wounding rates

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