Cooperative Fish and Wildlife Research Units Program: California
Education, Research and Technical Assistance for Managing Our Natural Resources

California Project

Redwood Creek Life Cycle Monitoring - DIDSON

April 2011 - March 2014


Participating Agencies

  • California Department of Fish and Game

The Redwood Creek watershed in Humboldt County is considered an important watershed for anadromous salmonids in northern California. It supports self-sustaining populations of coho salmon, Chinook salmon, steelhead and coastal cutthroat trout in addition to other native fishes. There are no hatcheries in the watershed, although hatchery stocks of salmon and steelhead do stray into the stream each winter. Salmon and steelhead in the Redwood Creek watershed are recognized as important for recovering populations of anadromous salmonids throughout northern California (Cannata et al. 2006). The pattern of land ownership within the Redwood Creek watershed presents opportunities for restoration. Ninety-six percent of the land area of the lower basin is in state and federal park ownership, and watershed restoration is being actively implemented on these lands. Although 51% of the upper basin is in private ownership, a small number of land owners control most of these lands making restoration planning simpler than in watersheds having complex ownership patterns. Watershed restoration actions have and are also being implemented in the upper watershed. An understanding how the environmental influences salmon and steelhead is necessary to inform restoration actions. The environmental influences on salmon and steelhead include those operating on freshwater environments as well as on marine environments. Understanding the response of salmon and steelhead to these factors requires monitoring of at least two life stages. Due to its size and compliment of ssteelhead and salmon species, Redwood Creek offers opportunities for monitoring and developing techniques for monitoring. The Redwood Creek watershed, at 285 m2, is representative of northern California watersheds, being near the median size of rivers in the SONCC coho domain. It is large enough to support a diversity of species of salmonids, with some having moderate population size. It is also large enough to present challenges in monitoring fish populations. Our objective is to monitor escapement of adult salmon and steelhead to Redwood Creek. Escapement estimates will be made using dual frequency identification sonar (DIDSON) imaging system.