Did Feds Sandbag the numbers supporting the Significant Decline Triggers to keep dam breaching at bay?

The Obama Administration submitted its plan to the Federal court Sept. 11 on management of the Federal dams.  For the most part they embraced the plan developed by the Federal dam agencies during the Bush Administration.

An addition to the plan was an Adaptive Management Implementation Plan (AMIP) to infuse accelerated activities to conserve salmon.  The AMIP addresses the always controversial topic of removing the four Lower Snake River dams.  Buried in the AMIP is a contingency that if fish runs decline significantly in the next ten years a series of actions will be triggered, and reportedly last on the list is a plan to initiate a study about removing one or more of the lower Snake River dams.

For wild/naturally spawning Snake River Spring/Summer Chinook salmon, the AMIP sets an Early Warning indicator of 7,575 fish for a four-year running average.  A Significant Decline Trigger is set at 4,850 fish.  These numbers are at the 80th and 90th percentile (lowest) respectably, based on data from Lower Granite Dam fish counts 1982-2008.  There is no stated biological basis for these levels, and higher fish counts at the 50th or 60th percentiles can easily be justified when looking at the large number of subpopulations that chinook salmon seperate into when heading to spawning areas over thousands of square miles.

The metrics are based a time frame that ignores data from earlier years.  If all the data were used the Early Warning indicator rises to 7,925 fish and the Significant Decline Trigger jumps to 5,875 (see comparison charts above).  The Feds use a fish count starting in 1979, coincidentally the year the fish returns were an all-time low (later broken in the even worse mid-1990s).  They exclude the earlier years when there were more fish returning.  If the full data set is used the Significant Decline Trigger number rises and therefore a greater chance that the number will be reached, a prospect the Feds appear to want to avoid.  But ignoring the information sets up the same legal vulnerability that existed in 1994 when the state of Idaho sued and won in court over the Feds illegal salmon plan.