Last updated on 4 October 2011
Since 1977, the salmon fisheries off the coast of Washington, Oregon, and California have been managed under the Pacific Coast Salmon Fishery Management Plan of the Pacific Fishery Management Council (PFMC) (PFMC 2012b), created by the Magnuson-Stevens Act of 1976 and reauthorized in 2007. The main goal of the PFMC is to manage all fisheries in both fresh and marine waters to achieve a level of adult spawner escapement associated with the maximum sustainable yield for salmon stocks under its management control. A number of biological reference points are used to guide and facilitate this process. However, escapement goals are not always biologically based, and many goals currently in place for stocks that are under the purview of the Pacific Salmon Commission (PSC) have not been reviewed and approved by this body (CTC 2013).
Escapements are measured for most of the major stocks in the fishery. There are persistent difficulties in counting escapements for California coastal Chinook salmon systems, and the Klamath River is used as a surrogate for assessing fishery impacts on this Endangered Species Act (ESA)-listed stock (O’Farrell et al. 2012).
Genetic stock identification programs continue to be developed and expanded to estimate the stock composition of commercial catches off of the Pacific west coast (PFMC 2012a). As part of the Genetic Analysis of Pacific Salmonids (GAPS) project, 13 microsatellite loci have been identified that can be reproducibly assayed in genetic laboratories, resulting in 110 identifiable Chinook salmon populations coastwide (Seeb et al. 2007). Systematic genetic sampling of catches effectively began in 2010 (data were not collected in 2008 and 2009 due to widespread fishery closures off of Oregon and California) (PFMC 2012a). Meanwhile, coded-wire tagging programs continue to provide stock composition estimates for all coastwise fisheries (PFMC 2008b; Nandor 2010).
Last updated on 13 March 2014
Management recommendations made by the PFMC (PFMC 2013a and 2013b) are guided by objectives of the council’s Pacific Coast Management Plan (Salmon FMP), but also defer to obligations of the Pacific Salmon Treaty (PST) (PST 2013) and protections required under the Endangered Species Act (ESA) (see “Recovery Plan” section below).A main task of the PFMC is to set annual allowable catch limits forKlamath River fall and Sacramento River fall Chinook salmon, each of which is an indicator stock representing one of the two southern stock complexes (PFMC 2012b). The determination of the Klamath River Fall Chinook salmon target catch in 2012 provides an example of how this is done (see PFMC 2013a). The total ocean abundance of age 3, 4, and 5 Chinook salmon was estimated to be slightly over 1.65 million salmon for that year, yielding an expected 270,000 returning spawners, which exceeds the abundance required to open the fishery. There is a minimum escapement goal of 40,700 adult salmon in place for the run. Meanwhile, the target exploitation rate is 0.68, resulting in a target escapement of 270,000 x (1-0.68) or about 86,400 adult Chinook salmon. Thus fisheries impacting Klamath River Fall Chinook salmon were managed to achieve this escapement number. Failure to come within 10% of this goal would result in characterization of the stock as overfished.
Management guidelines are discussed and evaluated by three entities: the PFMC’s “Council” and advisory bodies and the PSC’s Chinook Technical Committee (CTC). The PFMC’s Scientific Technical Team (STT) and Model Evaluation Workgroup (MEW) are advisory bodies that provide analytical and management expertise to voting members of the Council when evaluating proposed management measures and assessing the effect of these measures on past fisheries (PFMC 2014). Two models are used in these assessments: the Fishery Regulatory Assessment Model and the Klamath Harvest Rate Model (PFMC 2008a and 2008b, Prager and Mohr 2001; Mohr 1997). Meanwhile, the CTC evaluates the status of Chinook salmon stocks from Cape Falcon, Oregon, to Alaska and the impact that proposed fishery regimes will have on these stocks (PST 2013). The Chinook Model is the analytical tool developed for this work (CTC 2012).
Although the timing and distribution of stocks or stock complexes in the various fisheries are well understood (Myers et al. 1998; Williams et al. 2011), appropriate escapement goals and optimum production levels remain to be determined.The Klamath and Sacramento fall Chinook salmon escapement goals are simply a base-year average escapement.Meanwhile, depleted stocks located between the Canada border and Cape Falcon, Oregon, are managed under a PST goal established in 1999 to reduce exploitation rates to 60% of base period (1978-1982) rates (PST 2013). The PSC is the entity charged with implementing PST provisions and monitoring the status of PST stocks. Many of these Washington and Oregon stocks do not have escapement goals that have been reviewed and approved by the PSC (CTC 2013).Uncertainty in hatchery production and the accuracy of natural stock escapement estimatesare challenges to the process of establishing appropriate escapement goals.
Last updated on 13 Mar 2014
There have been substantial decreases in escapements for some key Chinook salmon stocks or stock groups since 1998 (Figures 1-3). In fact, the escapements for nine stocks are weak enough to have merited listing as either threatened or endangered under ESA guidelines (PFMC 2012b). These stocks include California coastal, Sacramento River Central Valley spring-run, Lower Columbia River Natural Tule stock, Upper Columbia River spring-run, Puget Sound stocks, Sacramento River winter-run, Snake River fall-run, Snake River spring/ summer-run, and Upper Willamette River Chinook salmon stocks.
Even key index stocks that are not listed, such as the Sacramento River Fall Chinook run failed to meet the minimum escapement goal from 2007 – 2009 and 2011 (PFMC 2013c). We assessed escapement trends of stocks and stock groups using the robust regression analysis methods of Gieger and Zhang (2002). Sacramento/ San Juaquin stock complex has been declining at a rate of 6.4% per year (Figure 1). The Klamath River Fall Chinook run has been declining at 3% per year, although a strong return in 2012 helps mitigate this decline (Figure 2). The threatened Puget Sound stock group as a whole is declining at 4.7% per year (Figure 3) with some drainages exceeding 6% per year (not shown; results are based on CTC escapement data (CTC 2013)). The Green River (6.5%) and Nooksack River (7.2%) show the largest declines.
Figure 1: Total escapement of Sacramento/San Joaquin River Chinook salmon (all runs combined), 1998–2012 (PFMC 2013c; CDFW 2013). A Geiger and Zhang robust regression (Geiger and Zhang 2002) is superimposed on the data set.
Last updated on 4 October 2011
Stock status for salmon is assessed based on multi-year escapement trends and performance against escapement goals (see synopsis under reference point section). There are a number ESA listed stocks impacted by the fishery. See "Recovery Plan" section for more detail.
Last updated on 04 Oct 2011
There has been a precipitous decrease in total troll Chinook salmon catches since 2006, and these decreases are concurrent with decreases in escapements and the failure of a number of stocks to meet escapement goals. The 1998–2005 catches averaged about 638,000 Chinook salmon while the 2006–2012 catches averaged 153,000 fish, or less than 25% of the earlier catches (Figure 6).
Figure 6: Total (hatchery and wild) Chinook salmon troll catch by PFMC management area, 1998–2012. Data are from Appendix A of PFMC Stock Assessment and Fishery Evaluation documents (PFMC 2006 and 2013c).
Decreases in catch of natural-stock Chinook salmon areeven greater, with the average 2006–2012 catch amounting to only 16% of the 1998–2005 average catch (Figure 7).
Figure 7: Wild Chinook salmon troll catch by PFMC management area, 1998–2012. Catch of natural stocks was calculated as the difference between total commercial catches (data from Appendix A in PFMC 2006 and 2013c) and hatchery catches (RMPC 2013).
Decreases in catches from the management areas south of Cape Falcon averaged over 5% per year, or a total of 80% decrease in catch over the last 15 years. Meanwhile, the Chinook salmon catches from the management area between Cape Falcon and US/Canada border has increased slightly over the 15 years, averaging 3.2% increasing trend over these years.