Studies of fish use in Puget Sound pocket estuaries began in 2002. At first, research was limited to understanding juvenile Chinook salmon use of sites within Skagit Bay (Beamer et al. 2003). In 2004, the study expanded to sites throughout the Whidbey Basin, Fidalgo Bay and Samish Bay via a cooperative effort that was partially funded by the Northwest Straits Commission4. The focus of this expanded research is to understand landscape scale patterns of fish usage including what species and life history types use these systems, how connectivity or position within the larger landscape affects fish use, and how patterns of fish use relate to protection and restoration of these areas. This expanded research effort has continued throughout 2007 and included sampling in Elger Bay with the help of Island County WSU Beach Watchers. The focus of this report is on fish abundance and size in Elger Bay from 2005 through 2007. Although we primarily report only fish abundance and fish size in this one system, we also briefly consider results within the context of the larger study of pocket estuaries.
Study area
Elger Bay is part of the Puget Sound nearshore (Figure 1). The Puget Sound nearshore, as defined by the Puget Sound Nearshore Ecosystem Restoration Program, includes the Puget Sound fjord, Hood Canal, Whidbey Basin, the Strait of Juan de Fuca, the San Juan Islands, and the mainland coast to the Canadian border. Within the nearshore, coastal and upland processes interact to form a diversity of intertidal, subtidal, and terrestrial habitats. Coastal processes (wind waves, tides) help create coastal landforms such as spits, dunes, tidal channels, and salt marshes, while watershed processes (streams, groundwater seeps, rivers) contribute freshwater to the nearshore and create landforms like delta flats, marsh islands, and distributary channels.
From a geomorphic perspective, we consider Elger Bay to be one of several tidal channel lagoons which are part of a group of nearshore habitats we commonly refer to as pocket estuaries. Pocket estuaries are partially enclosed bodies of marine water that are connected to a larger estuary (such as Puget Sound) at least part of the time, and are measurably diluted by freshwater from the land at least part of the year (after Pritchard 1967). These small estuaries are differentiated from larger estuaries as the watersheds they are associated with are not Chinook salmon spawning habitats (Beamer et al. 2003). Pocket estuaries like Elger Bay are an important habitat for wild Chinook salmon fry early in the year once they leave their natal estuary and enter nearshore areas of Puget Sound (Beamer et al. 2003 and 2006).
Kagley, A., Zackey, T., Fresh, K. and Beamer E., 2007. Juvenile salmon and nearshore fish use in shoreline and lagoon habitat associated with Elger Bay, 2005-2007. Northwest Fisheries Science Center, Seattle, WA. pp. 26.
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