Skagit River delta wetland extent, 1850-2010

Aerial photograph of the Skagit River delta, in the Puget Sound area of Washington, superimposed with geographic information system (GIS) data that illustrate changes between 1850 and 2010. In 1850 the delta included extensive wetlands providing important habitat for salmon spawning (orange color). By 2010 most of the delta had been “reclaimed” for development by a system of dikes and levees (red lines), greatly reducing the habitat available to salmon.