Thursday, August 23, 2012

Washington State Wild Steelhead Status

Washington State Steelhead Status
Washington Steelhead Management Plan

“In 2004, the Director of the Washington Department of Fish and Wildlife challenged the agency to develop a scientific foundation for a Statewide Steelhead Management Plan (SSMP). The scientific foundation for the SSMP comes from the Department’s steelhead science paper “Oncorhynchus mykiss: Assessment of Washington State’s Anadromous Populations and Programs” (Draft February 2, 2008), which provided several findings and recommendations to rebuild Washington’s wild stocks. The findings and recommendations represent the underpinnings of the Statewide Steelhead Management Plan.
“The steelhead management plan is necessary because in spite of seventy years of conservation efforts directed at the state’s steelhead stocks, many of these stocks are at a fraction of their historic numbers. Five of the seven distinct population segments that exist in Washington are currently federally listed under the Endangered Species Act.”
Scott, James, B. and William T. Gill. 2008. Oncorhynchus mykiss: Assessment of Washington State’s Steelhead Populations and Programs Washington Department of Fish and Wildlife. Olympia, Washington

Abundance and Productivity

Abundance and productivity are two of the four VSP characteristics that determine the health of natural populations and opportunities for sustainable fishing opportunities.  Productive, accessible habitat is essential for the long-term viability and productivity of steelhead populations.

Findings and Recommendations:

•  The status of steelhead populations varies substantially across Washington.  Over 90% of the populations in the Olympic Peninsula region and over 60% in the Southwest Washington region were rated as “Healthy”.  However, less than 20% of the steelhead populations were rated as “Healthy” in the five remaining regions of Washington.  Yet, recent data does suggest some reason for optimism.  Possibly due to improved marine conditions, the average escapement for steelhead populations throughout Washington increased by 48% in the years 1999 through 2006 relative to the prior 5 years.  (Chapter 8)

•  Population viability analysis identified thirteen populations of steelhead with the potential for substantive conservation concerns.  The population viability analysis (PVA) conducted for this paper can be used as a tool to filter data and identify populations with a potential conservation concern.  However, additional information is needed to fully assess the risk of extirpation.  PVA can be misleading, particularly  where population structure is uncertain or, as in the case with this analysis, the potential contribution of rainbow trout to population performance was not considered.  (Chapter 8)

Recommendation.  Conduct Status Assessments.  Reassess the status of all populations in Washington on a 4 to 8 year cycle to assure that opportunities for early action are not missed.  Use population viability analysis (PVA) to filter spawner abundance data and, for populations identified to have a potential conservation concern, broaden the analysis to evaluate the contribution of rainbow trout to population viability, the previous performance of the population, and factors affecting population status.  (Chapter 8)

Recommendation.  Formalize Assessment of At-Risk Populations.  Annually  monitor and review the status of populations at risk, identify limiting factors, and assess the effectiveness of management actions.  Recommend and implement new programs to address limiting factors, and potentially initiate
“rescue programs” like kelt reconditioning, natural stream channel rearing, or hatchery supplementation to conserve natural populations until limiting factors are addressed.  (Chapter 8)

•  The inability to monitor the escapement of populations introduces significant uncertainty and risk into the management of steelhead in Washington.  The status of 47% of the steelhead populations could not be rated because of the lack of a time series of escapement or other abundance data.  (Chapter 8)

Recommendation.  Improve Escapement Monitoring.  Prioritize monitoring, solicit funding, develop alternative estimation methods and sample designs, and enlist the assistance of other organizations to increase the percentage of populations assessed on a regular basis.  (Chapter 8)

Historic Abundance    Current Abundance    Average Decline

Grays Harbor (8 Rivers)
5,424                       17,993                  68%

Columbia River Mouth (6 Rivers)
13,706                       2,326                 56%

Southwest Washington (14 Rivers)    62%

Lower Columbia River Winter Steelhead (13 Rivers)

26,228                        5,218                73%

Lower Columbia Summer Steelhead (4 Rivers)

5,016                          2,412                 53%

LCR Winter and Summer (17 Rivers)  69%

Mid-Columbia Steelhead (6 Rivers)

100,409                      4,075                   87%

Upper Columbia Steelhead (4 Rivers)

18,838                           553                   98%   

Snake River Steelhead (4 Rivers)

 28,713                        1,910                    84%

Puget Sound
No data

Olympic Peninsula
No data

Bill McMillan’s assessment of these tables
            The “pre-settlement” steelhead numbers indicated in the 2008 WDFW estimates are clear indications of lack of research into available fishery history with a resulting example of what has been termed the shifting baseline syndrome.    As an example, in 1895 the Grays Harbor weight of steelhead canned was 395,479 pounds which at 8 pounds per winter steelhead (in the ballpark of what the average steelhead was at that time as indicated in the earliest literature) would represent 49,435 steelhead harvested alone.  If harvest was 50% of run-size it would mean a run-size of 100,000 steelhead to the Grays Harbor system of streams.  If harvest was 70% of run-size it would be 70,621 steelhead.  This does not take into account the thousands of steelhead that were used for subsistence, fertilizer, and to feed livestock by the settlers of the region which in Puget Sound was estimated in an 1895 U.S. Fish Commission report to be equal to all the commercial steelhead catch that year on the Stillaguamish River.  This was further confirmed as likely the case from other historic sources.  It also does not include the tribal subsistence fisheries at that time.  From the historic catch data of 1895 the probable realistic range of numbers of steelhead returning to the Grays Harbor system would have been 140,000-200,000 steelhead.
            The WDFW pre-settlement estimated run-size for the Grays Harbor systems is 17,993 steelhead, or 36% of what the reported commercial catch alone was in 1895.  WDFW indicates that the present wild steelhead run-size of the Grays Harbor systems is 5,424 steelhead and represents 68% loss of that at the pre-settlement period.  In fact, that estimate of 5,424 steelhead is 2.7-3.9% of what the wild steelhead run-size range more likely was at the time of 1895 at Grays Harbor, or 96.1-97.3% loss of former wild steelhead numbers.  This is consistent with the steelhead losses found by Gayeski et al. 2011 for the Nooksack, Skagit, Stillaguamish, Snohomish, and remainder of Puget Sound streams that have occurred since 1895. 
            As another example, in the winter of 1953-54 the Queets River of the Olympic Peninsula had a reported tribal catch alone of 13,182 wild winter-run steelhead.  In 1923 a cannery was in operation on the Queets River with 72,000 pounds of canned steelhead packed that would have represented 240,000 pounds of live steelhead if there was 70% wastage as can potentially occur.  Queets steelhead were found to average 9.8 pounds in the tribal catch of the 1930s and 1940s, somewhat larger average than typical for Puget Sound.  The 1923 cannery pack would have represented 24,490 wild steelhead.  If the cannery pack was 50% of the run-size some 48,980 steelhead returned to the Queets that year.  This does not include tribal subsistence catch or that of settlers in the area and is therefore very conservative.
            Wind River in the USFWS surveys of the Columbia River basin during the 1930s was estimated to have sufficient available gravel for about 15,000 spawning salmon based on the size of the average Chinook salmon redd (larger than that for steelhead).  At that time the only fish that had access to the majority of Wind River basin that is above Shepard Falls was summer-run steelhead.  That estimate of Wind River productivity based on available spawning gravel did not include Trout Creek basin now known to be one of the major producers of steelhead.  Therefore the 1930s estimate was conservative.  In 1951 it was estimated that Wind River had an escapement of 2,500 wild summer-run steelhead after a sport harvest of 7,500 pounds, or about 1,000 steelhead for a total of 3,500.  By 1951 Wind River was already in great steelhead decline, and the 1951 return had yet to benefit significantly from removal of the Carson Lumber Company mill dam near today’s Cannavina Road that had denied upstream passage since at least the 1930s to the majority of the best mainstem Wind River spawning habitat.  How WDFW came up with a pre-settlement run-size figure of 2,404 wild summer-run steelhead to Wind River is difficult to determine. 
            Regarding the Eastside streams the estimates are not as far off as for the Westside.  Nevertheless, they have commonly been low-balled.  As one example, Idaho’s Clearwater River as late as 1960 had an escapement of 45,000 wild summer-run steelhead past Lewiston Dam.  This was after the impacts of the commercial fishery in the lower Columbia, Columbia River sport fisheries, and the Snake River sport fishery.  It was long ago noticed in 1895 and 1896 U.S. Fish Commission reports that salmon and steelhead returns to the Columbia and Snake basins had collapsed since 1883 and that the last large returns were in 1878.  1960 was long after these known collapses.   Based on the 1960 steelhead numbers that remained, 19th century Clearwater run-sizes of wild steelhead in the 200,000 range are realistic.  The Clearwater basin provides a low end measure of what the Yakima basin may have once provided.  Nevertheless, estimates based more on available spawning gravel as one relatively easy habitat measure of productivity may in the future provide estimates of more scientific justification – both historically and at present. 
            These are just a few examples of how WDFW and other Northwest fishery managers have low-balled wild steelhead and salmon productivity prior to habitat alterations and subsequent hatchery impacts.  This is precisely what Daniel Pauly came to term the “shifting baseline syndrome” in 1995 as a worldwide fishery phenomenon that denies the ability to prevent a continuous decline in both salt and fresh water fish populations and similarly prevents recovery as we progressively downgrade fish productivity by using faulty historic baselines.

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