Invasion

Invasion Description

1st Record: Salem/OR/Willamette River (1888, Lampman 1946), 1st Record: Brandon Marsh National Wildlife Refuge/OR/Coquille River estuary (2007-2013, Silver et al. 2017)

Geographic Extent

Salem/OR/Willamette River (1888, Lampman 1946); Columbia Cascades (mow near Bonneville Dam/OR/Columbia River (Lampman 1946); Portland/OR/Willamette & Columbia Rivers (900, Lampman 1946; Hughes and Gammon 1987; Farr and Ward 1992); Cowlitz county/OR/Columbia River (2005, USGS Nonindigenous Aquatic Species Program 2018); Deer Island Slough, northwest of Columbia City off hwy 30 at Reichold Chemical (access only at south end)/OR/Columbia River (2013, USGS Nonindigenous Aquatic Species Program 2018); (R.M. 54) at Crims Island [~7 miles below Longview, WA/OR/Columbia River (2003, USGS Nonindigenous Aquatic Species Program 2018); Crimms Island (downriver from Longview WA/OR/Columbia River (2004, Haskell and Tiffin 2011); along highway 30 at Prescott Junction, west of Trojan Nuclear Power Plant. north of hwy 30, near Westport, 10 miles west of Clatskanie/OR/Prescott Slough, Columbia River, (2001, USGS Nonindigenous Aquatic Species Program 2014)); OR/Westport Slough (2001, USGS Nonindigenous Aquatic Species Program 2014); north of Knappa/OR/Grizzly Slough, off Blind slough, Columbia River (2001, USGS Nonindigenous Aquatic Species Program 2014); Astoria/OR/Columbia River mouth (1936, USGS Nonindigenous Aquatic Species Program 2014), Brandon Marsh National Wildlife Refuge/OR/Coquille River estuary (2007-2013, Silver et al. 2017)