Habitat use by juvenile salmon in the Columbia River Estuary: Columbia River Channel Improvement Project research

Beach seine surveys to examine fish community composition were conducted at six sites near the oligohaline/euryhaline transition zone of the Columbia River estuary within Cathlamet and Grays Bays (RM 22-25) during September 2003 and May, July, and August 2004. Three sites (2004 only) were also sampled in the tidal freshwater zone of the estuary near Wallace Island, Oregon (RM 46-48). Beach-seine sites were selected within each zone to represent relative degrees of exposure to tidal currents and wave energy (exposed, semi-exposed, or protected) based on proximity to the deep shipping channel and on topographic features that could dampen water velocities (e.g., peripheral embayments, island complexes, and backwater areas).