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Evaluation of the 2003 and 2004 Chinook Mark-Selective Fisheries, Marine Areas 5 and 6 Final Draft

Category: Fishing / Shellfishing - Selective Fishing

Date Published: January 14, 2005

Number of Pages: 36

EXECUTIVE SUMMARY:

During the summers of 2003 and 2004, a mark-selective Chinook salmon Oncorhynchus tshawytscha ("Chinook") recreational fishery was implemented in waters of the Strait of Juan de Fuca with the objectives of: 1) increasing meaningful recreational opportunity while meeting conservation goals for Puget Sound Chinook salmon defined by the Puget Sound Chinook Harvest Management Plan; and 2) collecting information necessary to enable evaluation and planning of future potential Chinook mark-selective fisheries. The 2003 Chinook Mark-Selective Fishery started on July 5, 2003 and ran continuously through August 3, 2003 in Marine Area 5 and the western portion of Marine Area 6. The 2004 Chinook Mark-Selective Fishery started on July 1, 2004 and ran continuously through August 8, 2004 in the same areas. Marine Areas 5 and 6 (hereafter: Areas 5 and 6) are located in Washington waters of the Strait of Juan de Fuca, running from the Sekiu River easterly to Low Point, and from Low Point to approximately Whidbey Island, respectively.

Anglers were allowed to retain two marked (adipose fin clipped) Chinook > 22" (56 cm) as part of their daily limit, and were required to immediately release, unharmed, any unmarked Chinook caught. During the Chinook Mark-Selective Fishery anglers were also allowed to retain pink O. gorbuscha, sockeye O. nerka, and marked hatchery coho O. kisutch salmon.

This report focuses on evaluating the two years of the pilot Chinook Mark-Selective Fishery. Some general comparisons to the 2001 and 2002 non-selective Chinook fisheries in Area 5 are presented for the purpose of evaluating success of the Mark-Selective Fishery with respect to the general objective of increasing recreational opportunity compared to non-selective alternatives. We also compared alternative methods for determining mark rates and encounters with sublegal-size fish. Expected impacts of the mark-selective fishery from the Fishery Regulation Assessment Model (FRAM) pre-season planning tool are compared with the measured outcomes. Finally, recommendations for applications to future mark-selective fisheries are also presented.

Angler opportunity increased three ways due to this selective fishery. First, recreational Chinook fishing opportunity was expanded from 10-day and 5-day seasons in 2001 and 2002, respectively, to 30-day and 39-day seasons in 2003 and 2004, respectively. Second, anglers harvested nearly twice as many Chinook in 2003 and 2004 than they did in 2001 and 2002. Third, a portion of Area 6 was open for Chinook retention during the summer compared to all of Area 6 being closed for Chinook retention during the summer in 2001 and 2002. Increases in effort were modest compared to 2001 but approximately double the effort levels observed in 2002. Other than simply having more days of fishing open for anglers, the increased opportunity is attributable to a relatively high mark rate of approximately 45% for legal-size Chinook and reasonably good catch rates (approximately one retained Chinook for every 7-8 anglers).

Success of the Pilot Project is also indicated by the results of WDFW public education and Enforcement activities. Information collected by the Enforcement program and from creel surveys over these two seasons indicated consistently high compliance with not retaining wild (unmarked) Chinook during the fishery.

Since the impacts on Chinook stocks are based on assumptions about the overall level of angler encounters with unmarked Chinook, we estimated the number of unmarked Chinook encounters and compared those estimates with the pre-season FRAM expectations. Except for the unmarked sublegal-size fish in 2003, the estimates of encounters of unmarked legal-size Chinook and unmarked sublegal-size Chinook were below predicted levels.

We tested the assumption that test boat catches were representative of angler catches and found that for marked legal-size Chinook they were similar, suggesting they were probably similar for unmarked fish and sublegal-size fish as well. In strata with sufficient sample sizes for comparison, estimates of mark rates and ratios of legal/sublegal-size derived from test boat data and Voluntary Trip Report (VTR) information were very similar. We recommend a more rigorously structured VTR program that includes training and certification by WDFW staff. Based on our findings, we recommend that test fishing or VTR data, or a combination of both, be used to provide information on both mark rates and legal/sublegal-size categories in future Chinook Mark-Selective Fisheries.

In conclusion, this mark-selective Chinook fishery was successful at many levels. First, we met our two primary objectives of increasing opportunity and collecting the information necessary to evaluate pertinent biological impacts, including impacts to coded wire tagged Chinook. Second, we have likely captured the magnitude of this mark-selective fishery in terms of effort and harvest, and that magnitude was similar to pre-season expectations. Third, a level of enforcement was achieved to ensure that angler compliance with fishing regulations was high. Fourth, we were able to evaluate two different methods of obtaining mark rates and legal to sublegal ratios, and they were very similar when sample sizes were sufficient. And finally, although dependent upon factors unique to the proposed area, season, stock composition, and management logistics, our findings have provided a solid foundation for building successful mark-selective Chinook fisheries in the future.

Suggested Citation:
Evaluation of the 2003 and 2004 Chinook Mark-Selective Fishery, marine areas 5 and 6. Final Draft. January 14, 2005. Washington Department of Fish and Wildlife. 2005. Olympia, Washington.