USDA Forest Service

Pacific Southwest Research Station
Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
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Research Topics Wildlife & Fish

Predicting Effects of Trinity River Restoration on Bird Populations

Willow Flycatcher - Empidonax traillii. Copyright Michael J. Hopiak, CLO

Our goal is a predictive model of changes in bird presence and abundance with the progression of riparian habitat succession. This will provide a valuable tool for adaptive management.

In 1963, the Lewiston and Trinity dams were completed on the Trinity River, greatly reducing the flow and altering the habitat, including increased riparian habitat. One of the goals of the Trinity River Restoration Program is to "restore the fish and wildlife populations in the Trinity River Basin to levels which existed prior to construction of the dams". The Program proposes to do this by bank rehabilitation, including removal of large areas of riparian habitat, and river flow manipulations that may affect the wildlife species in the 63 km downstream of the dam.

Many of the birds in the basin depend on riparian habitats along the river for reproduction and migration (Miller et al. 2004). The breeding success and migration patterns of these birds are likely to be affected by restoration activities that temporarily or permanently alter the structural configuration, spatial distribution, and patterns of succession in the riparian habitat.

In 1990, we established baseline information on the wildlife species, including birds, in the Program area. Since 2002, we have been gathering data to quantify the relative abundances and habitat relationship patterns of bird species closely associated with riparian vegetation in cooperation with the Klamath Bird Observatory and others.

Together, these data sets have allowed development of a sampling design for monitoring changes in the avian community. Monitoring results can then be used for adaptive management, a key element of the Program’s strategy.

Reports and Publications
  • Miller, Sherri L., C. John Ralph, and Pablo A. Herrera. 2002. Trinity River Restoration Program avian monitoring - 2002 report. Submitted to the U.S. Fish and Wildlife Service, Arcata Field Office and the Trinity River Restoration Program Management Team. Unpublished report available from U.S. Forest Service, Redwood Sciences Laboratory, Arcata, California.
  • Miller, Sherri L., C. John Ralph, and Pablo Herrera. 2007. Predicting changes in bird abundance caused by removal and succession of riparian habitat (abstract). Proceedings of the First Annual Science Symposium of the Trinity River Restoration Program (TRRP), February 7-9, 2007, Weaverville, California.
  • Miller, Sherri L., C. John Ralph, Pablo Herrera, Bill Hogoboom. 2007. Predicting bird abundance associated with Trinity River restoration. p. 32 in Kevin Shaffer, Ann Chrisney, and Lisa Owen Vianni, eds. Proceedings of the Riparian Habitat Joint Venture Conference: Integrating Riparian Habitat Conservation and Flood Management in California December 4-6, 2007; Sacramento, California. 115 p.
Last Modified: Aug 29, 2016 11:26:16 AM