Baker Bay is a large, shallow estuarine bay located on the north side of the Columbia River Estuary
just upstream from the river's mouth from about river mile 2 to river mile 7. Major habitats are estuarine mudflats and emergent wetlands, with some open marine water. Broad expanses of mud flats are exposed at low tides. Tidal marshes totaling about 330 ha fringe the Bay except where intensive development occurs. The bay is dotted with rotting old pilings that provide perches for bald eagles. Marsh vegetation includes three-square bulrush, Lyngby's sedge, and Pacific silverweed. The Chinook River, with its associated estuary, enters the bay on the northeast side. The Chinook Estuary is largely in public ownership and is slated for restoration. Commercial crabbing and fishing and tourism are the major industries in the area. Although the bay is located on the Washington side of the river, the Oregon state line passes through the outer (southern) part of the bay. Thus, about 25% of the bay, including its two major islands (Sand Island and East Sand Island), are in Oregon. The proposed IBA site includes all of the Washington portion of the bay and its fringing tidal marsh that is public (state) land.
A habitat change analysis (1890 vs. 1992 habitat maps for the lower 46 river miles) determined tidal swamp and tidal marsh habitats have suffered the largest relative declines. This means that opportunity for juvenile salmonids to use these areas, i.e., accessibility, has been diminished. This habitat decline is due mostly to diking, filling, and flow regulation. These actions effectively eliminated the exchange of water, materials, and organisms between the larger aquatic system and the adjacent, shallowly vegetated habitats, although some exchange occurred through tide gates. Exchange is important not only for the access and use of these habitats by fish, but also for maintenance of habitat-forming processes such as sedimentation and erosion. By restoring tidal exchange, these processes are re-established, and the habitats can develop naturally as well as provide their functions to the ecosystem.
Department of Natural Resources & Waters of the State.