Five Year Status Reviews: Overview and Steelhead DPS Summaries

Tom Cooney, Northwest Fisheries Science Center of NOAA Fisheries

Read the presentation 2012kb

Section 4 of the Endangered Species Act (ESA) requires that the responsible federal agency for a species listing conduct a status review at least once every five years to determine whether there should be a change in listing status.   In August of 2011, NOAA Fisheries released the results of the most recent status reviews for west coast listed salmonid species.   Regional sets of reviews were based on updated analyses of ESU/DPS viability developed by the Northwest and Southwest Science Centers, respectively.  Domain teams of NOAA regional office specialists reviewed updated information on the specific ESA listing factors for each ESU/DPS and summarized their findings.  Information from these two basic sources provided the basis for NOAA listing determination conclusions.

The 2011 five year status reports differed from previous version in several respects.  First, the most recent review was initiated as a relatively quick overview of key status indices relative to findings in the prior review.  If those patterns indicated significant change from the prior review, a more detailed assessment likely involving a full biological review team would be convened.   Second, the 2011 review represented a transition from relying almost exclusively on a standardized but relatively simple set of biological abundance and trend metrics towards incorporating recovery objectives and metrics provided in formal recovery plans and/or technical recovery team reports.  As a result, those reviews include an increased emphasis on hierarchical organization within ESUs (strata, population groups etc.) and more detailed criteria for spatial structure and diversity.  As with prior reviews, each ESU/DPS chapter summarizes prior conclusions regarding key factors for decline and briefly discusses new information relative to those factors or their biological effects.  The NWFSC has highlighted several areas for additional development to improve the scope of future five year review reports including efficient exchange of annual data on populations, expanded treatment of regional recovery plan criteria and incorporation of indices of habitat conditions directly relevant to species status.

For the Upper Columbia DPS the updated trend in natural abundance remained positive, largely driven by relatively high survivals from the late 1990s brood years.  Hatchery proportions in natural spawning areas remain relatively high for 3 out of the four populations.  All four populations remain below viability objectives contained in the recovery plan adopted in 2005.  Population level estimates of annual abundance were available for only 2 populations in the Snake River DPS, although counts at Lower Granite Dam provide an aggregate estimate of returns to the DPS.  Trends were generally positive, although the aggregate return levels indicate that many populations are likely below recovery objectives.   The Middle Columbia Steelhead DPS includes four major spawning groups of populations.  Recent trends in natural abundance varied by MPG: abundance increased for all four Yakima basin populations.  Trends in the John Day, Umatilla Walla Walla and Eastside Cascade major population groups were neutral or moderately negative for specific populations.  Diversity risks for the Snake and Middle Columbia DPSs vary considerably across populations and MPGs based on information from juvenile sampling, inferences from habitat conditions and the proximity of some populations to major hatchery programs.  Recent year natural abundance estimates for Willamette and Lower Columbia River DPS populations were also down from peak levels in the early to mid-2000s, returning towards the levels prevalent at the time of listing.  The Puget Sound Steelhead DPS was listed in 2007, as a result the status review was the first since listing.  Four of the 15 populations with sufficient data to estimate trends remain at relatively low natural abundance and 6 of the 16 populations exhibit declining trends in recent years.  Assuming those declining trends continue, projected population extinction risks are moderate to high, especially for the proposed populations in the south Puget Sound and Olympic major population groups.