Puget Sound Chinook Harvest Management Performance Assessment 2003-2010

This report assesses Puget Sound Chinook harvest management performance for management years 2003-04 through 2010-11. Comparison of pre-season and post-season (validation) FRAM estimates of total and southern U.S. exploitation rates can determine if the ceiling rates stipulated by the Harvest Plan have been exceeded, and whether there is consistent positive or negative deviation for a given management unit. For this recent time period, post-season deviations from pre-season rates vary widely for a given management unit, but they are not consistently negative or positive. Generally, validation runs indicate that SUS or total exploitation rate ceilings have not been exceeded, but such incidents are examined below.

Deviations from projected commercial and recreational catch are also summarized to detect consistent differences that might be addressed by adjusting pre-season planning. Generally deviations for a given marine region or river are not consistently negative or positive. Forecast accuracy is also examined, based on uniformly obtained values of terminal abundance for each management unit. Forecast error also varies widely for each unit, but we did not detect consistent errors.

The current status of each Chinook population is assessed from the time series of estimates of natural escapement, to provide a context for assessing management error. We used adjusted estimates for many populations, and limited assessment of NOR escapement in particular to years when these estimates have been based on consistent methods and adequate carcass sampling. However, for many populations NOR abundance is uncertain.

Management response to critical status (i.e. implantation of the CER ceiling when projected escapement is lower than the Low Abundance Threshold) was appropriate in most cases. The Nooksack early and Mid Hood Canal management units were in critical status for 2003-2010. The Stillaguamish was managed under the critical ER ceiling in 2006-2008 and 2010, due to projected higher ERs associated with northern fisheries, or due to forecasted critical abundance for the fall stock. Pre-season models did not anticipate escapement below the LAT for the summer stock that was observed in 2007, 2009, and 2010. The Snohomish was managed under the critical ER ceiling in 2004-2009 due to higher ERs associated with northern fisheries. Observed escapement to the Skykomish was less than the LAT in 2007 and 2009. Pre-season models did not project the observed escapements to the Green River in 2009 and 2010 that were lower than the LAT. Projected escapement to the Dungeness was projected to be less than the LAT in 2003 and 2004, but actual escapement was higher than the LAT. Pre-season models did not anticipate that escapement would be less than the LAT in 2007-2010.

Fisheries that contributed to exceeding ER ceilings are described with reference to deviations from pre-season, fishery-specific harvest rates.