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Wild Winter Steelhead Run Timing

Wild Winter Steelhead Run Timing . How It Has Been Reshaped by Fisheries Management in Washington. Questions Examined:. When did hatchery steelhead significantly enter the catch What proportion of historic catches were prior to March Has there ever been differential harvest opportunity

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Wild Winter Steelhead Run Timing

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  1. Wild Winter Steelhead Run Timing How It Has Been Reshaped by Fisheries Managementin Washington

  2. Questions Examined: • When did hatchery steelhead significantly enter the catch • What proportion of historic catches were prior to March • Has there ever been differential harvest opportunity • Has a shift in wild steelhead run timing occurred • What are the biological values of early run timing Mid-Sauk River, Jan. 24, 2003

  3. Washington’s Historic Hatchery Steelhead • Steelhead fry releases began 1903; fingerlings 1936; not only was there little return but “Ironically, steelhead runs…were reduced by the hatcheries…” (Crawford 1979) • 1937-1941 Green River tagging study: “Artificial propagation appears to contribute very little towards the maintenance of steelhead trout populations.” (Pautzke & Meigs 1941) • 3.4% hatchery steelhead in Green River sport catch 1940; ~2% in 1941 (Pautzke & Meigs 1940; 1941)

  4. Pautzke and His Supertrout From Sports Illustrated Feb. 1955 “In 1950 he planted seven rivers. In 1953 he planted 760,000 … fingerlings in 35 rivers…”

  5. Historic Wild Winter Steelhead Run-TimingSport Catch 1955 & 1956: nine Washington steelhead rivers [WDG summaries]Tribal Catch 1934-1959: nine Washington steelhead rivers [Taylor 1979]Sport Catch 1954-1961: all Washington steelhead rivers [Royal 1972]

  6. Hoh River Tribal Steelhead Catch (1944-1959) • Hoh River Sport Steelhead Catch (1955 & 1956)

  7. Nisqually River Tribal Steelhead Catch (1935-1959) • Nisqually River Sport Steelhead Catch (1955 & 1956)

  8. Nooksack River Tribal Steelhead Catch (1951-1959) • Nooksack River Sport Steelhead Catch (1955 & 1956)

  9. Queets River Tribal Steelhead Catch (1934-1959) • Queets River Sport Steelhead Catch (1955 & 1956)

  10. Quinault River Tribal Steelhead Catch (1941-1959) • Quinault River Sport Steelhead Catch (1955 & 1956)

  11. Return of Marked Hatchery Steelhead and Wild Steelhead at 5 Rivers from Field Checks [Royal 1972] • Chambers Ck. stock hatchery steelhead available to the sport fishery earlier than wild with substantial % in December • The differential run-time provides an essential management tool

  12. Chambers Ck. stock hatchery steelhead available to the sport fishery earlier than wild with substantial % in December • The differential run-time provides an essential management tool

  13. Chambers Ck. stock hatchery steelhead available to the sport fishery earlier than wild with substantial % in December • The differential run-time provides an essential management tool

  14. Among the few Washington rivers that better fit the 1972 Royal model for potential differential harvest of hatchery steelhead were the 1956 Skagit & 1955 Dungeness River steelhead examples that were then largely wild • Nevertheless 56% of the largely wild Skagit catch & 50% of the Dungeness largely catch were Dec through Feb

  15. Steelhead ConsequencesOf Misinterpreting History • Today the majority of winter steelhead are caught in December and January and are as much as 90% hatchery steelhead [Crawford 1979]

  16. Hoh River Steelhead Management(30-35 years after 1962) • Interaction between wild & hatchery stocks is minimal because hatchery fish return earlier than wild & are managed for high exploitation (up to 95%) in terminal sport & commercial fisheries [McHenry et al. 1996] • Given high hatchery fish exploitation rate of about 80%, healthy wild spawner escapements, & difference in spawn timing of hatchery fish (Jan/Feb) & wild fish (mid Feb through May), potential for interbreeding is limited [Washington State Salmon and Steelhead Stock Inventory (SASSI) 1994]

  17. Queets River sport steelhead catch in 1955 & 1956 compared to 1995 & 1996 by monthly area of distribution • Differences in hypothetical bell curves in wild winter steelhead return based on catch

  18. Pysht River sport steelhead catch in 1955 & 1956 compared to 2001 & 2002 by monthly area of distribution • Differences in hypothetical bell curves in wild winter steelhead return based on catch

  19. Why Early Run Timing? • Provides option for early spawning to increase overall fit to broadest range of temperature and flow patterns • Can result in earlier emergence; larger size into 1st winter; & ability to migrate from/within intermittent streams • Can provide more staggered emergence & resultant staggered use of available food resources in critical 1st months • Provides for destination adjustments to fluctuating basin conditions (rainfall, temperature, volcanic episodes, landslides, etc.) • Provides males the opportunity for multiple spawnings over the broadest period of time & broadest area

  20. Lower Clearwater Sub-basin of Queets:Examples of Early Run Timing Importance[Cederholm 1984] • Spawning began in January in both the mainstem and tributaries but spawning peaked earlier in the tributaries • Spawning peak varied by tributary potentially reflecting differing flow/temperature/scour patterns • Warmest water year spawning peaked 39 days earlier than coldest year [steelhead entry time remained same each year as indicated by tribal catch] • Late emergence: small size going into 1st winter; Early emergence: large size going into 1st winter

  21. Steelhead redds in 5 tributaries of the Clearwater Basin in 1978 (only year both Jan. & Feb. trib surveys were made) • Differing spawn times in each of 5 Clearwater Basin tributaries in 1978

  22. Three Siuslaw Basin Tributaries on Oregon Coast Wild Steelhead Trapped on Creek Entry [Lindsay et al. 1991; 1992; 1993; & pers com Ken Kenaston ODFW] • Females thought to spawn within few days and leave • Males remained longer, including two that averaged 35 days • Early spawning may be needed to emerge prior to reduced flow

  23. Studies at Snow Ck. demonstrate steelhead mating complexity & that early arriving males are particularly successful • (Seamons et al. 2003 & 2004) • Variable dates of first steelhead arrivals: December-March • Males arrived avg. 15 days prior to female they mated with • Females mated with males that arrived before them • Males spawned with as many as 10 females • Females spawned with as many as 5 males • One early arriving male sired 40% of all YOY in study area

  24. Skagit River Basin [Phillips et al. 1980; & 1981] 75% steelhead spawn in tributary streams Skagit River Basin [Freymond 1984] Skagit River tributaries in 1983 had 13.7 redds/km; mainstem 9.2 redds/km Rogue River [Everest 1973] Greatest spawning intensity in small tribs: <25 sq mi; <50 cfs winter flow; dry by mid-June Many support large populations from which fry must migrate soon after emergence Early-Run/Tributary Relation

  25. The whole is the sum of its parts

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