Seminar and Lecture Series Schedule

Fishery Foundation of California (FFC) Presents:
Gualala: River Dead or Alive?

Learn the answer to this question, as revealed by biologist Richard W. DeHaven, during a 90-minute seminar soon in your local community.

Mr. DeHaven retired in 2004 after a 4-decade career with the U.S. Fish and Wildlife Service. In 2001 he initiated a 10-year population study of steelhead on the Gualala River along California’s north coast. Now, with the decade of data in hand, the 'dead or alive' issue can be addressed and additional facts revealed, including:

  • How many steelhead and coho salmon the river historically supported.
  • How many adult steelhead are returning to spawn today.
  • Why the river’s coho are essentially extinct, with little chance of returning soon.
  • New secrets of steelhead biology being uncovered.
  • Why traditional “band-aid” restoration efforts are failing.
  • What impacts are most effectively killing the river ecosystem.
  • What single habitat need should be the target of restoration efforts.
  • What novel, new strategy may be best for meeting this habitat need.
  • How mitigation banking may help save the river and its anadromous fisheries.

To date, seminars have been presented in Gualala, Davis, Sacramento, Santa Rosa, Santa Cruz, Vacaville and San Francisco. Additional seminars in other cities may be pending; please contact the author directly for a list of these (click below).

2009 CalNeva Chapter, American Fisheries Society Annual Meeting
Santa Rosa, California
April 1-3, 2009

Abstracts of Presentations:

Gualala River Steelhead Population Estimates from Counts in “Favored” Pools

Richard W. DeHaven
*U. S. Fish and Wildlife Service, Sacramento, California (Retired), Currently P. O. Box 4654, Davis, California 95617.

Abstract.–Adult steelhead migrating in small coastal rivers hold and rest in certain “favored” pools and runs; this behavioral nuance provides a basis for relatively quick and inexpensive population surveys. On the Gualala River, California, such surveys of adult steelhead have been conducted annually for eight years (2002-2009), along an 18.7-mile reach (Index Reach) of the Wheatfield Fork. Four to nine Index Reach surveys are conducted during each spawning season. A standardized survey protocol, based on a single observer counting fish from a small aluminum drift-boat, has been developed and implemented. Such surveys yield three population indices: mean annual count; expanded mean annual count; and peak annual count. In addition, with estimates of observer efficiency (OE=proportion of actual fish counted) and survey life (SL=time fish spend in the survey area) included, population estimates can be made, using area-under-the-curve (AUC) methodology. To date, the various metrics point to a highly variable annual return of adult steelhead to the river, a likely reflection of the river’s impaired ecosystem functioning and growing summertime dewatering problem. Another 2-4 years of surveys are planned, with a focus on improving OE and SL values (and thus AUC estimates) and identifying the best population metric(s) for long-term trend analyses.

Steelhead, population, survey, Gualala, Wheatfield

Guzzlers: Novel Strategy for Salmonid Restoration in the Gualala River, California?

Richard W. DeHaven
*U. S. Fish and Wildlife Service, Sacramento, California (Retired), Currently P. O. Box 4654, Davis, California 95617.

Abstract.–Eight years (2002-2009) of steelhead surveys on the Gualala River, California are showing that: populations are highly variable; spawner returns are largely driven by juvenile steelhead (JSH) production 2-3 years earlier; and JSH production responds positively to increased summertime stream flows with associated lower water temperatures. Yet summertime conditions for JSH are incrementally worsening in much of the watershed, as man’s influence incrementally reduces stream flows, thereby exacerbating water temperatures as a population-limiting factor. Nevertheless, wet years which produce JSH-friendly summertime flows and temperatures are still capable of generating subsequent robust adult spawner returns, as evidenced by the relatively large (>4,300) return of adult fish to the Wheatfield Fork (the largest of five forks) of the river in 2008. Thus, streamflow augmentation (SFA) may be a viable restoration strategy. The Fishery Foundation of California and Wildlands, Inc. are developing concepts (and beginning partnering for feasibility study) of a novel SFA strategy: small reservoirs dedicated to improving summertime conditions for JSH–a concept analogous to the “guzzlers” used for wildlife enhancement in arid areas. SFA reservoirs would be strategically placed in upstream and/or off-stream locations, used to capture excess wintertime flows, and managed to provide releases back into the stream at critical summertime periods. SFA needs would be governed by real-time monitoring of stream flows, water temperatures, weather patterns and JSH numbers. The SFA concept could also have a mitigation banking component, with a portion of the restoration benefits reserved for offsetting future impacts to the river from logging, vineyard expansions and other detrimental activities.

Steelhead, population, streamflow, Gualala, Wheatfield


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