Invasion

Invasion Description

1st Record: Portland/OR/Oswego Lake, Willamette River (1924, Chapman 1942; Lampman 1946; Hughes and Gammon 1987; Farr and Ward 1993), 1st Record: Brandon Marsh National Wildlife Refuge/OR/Coquille River estuary (2007-2013, Silver et al. 2017)

Geographic Extent

Portland/OR/Oswego Lake, Willamette River (1924, Chapman 1942; Lampman 1946; Hughes and Gammon 1987; Farr and Ward 1993); OR-WA/Willamette & Columbia Rivers (Chapman 1942; Lampman 1946; Hughes and Gammon 1987; Farr and Ward 1993); Cowlitz County/WA/lower Columbia (2005, USGS Nonindigenous Aquatic Species Program 2018); Crimms Island (downriver from Longview WA/OR/Columbia River (2004, Haskell and Tiffin 2011); Reaches B-H, lower to uppermost estuary/OR-WA/Columbia River (2010-2016, Sol et al. 2021), Brandon Marsh National Wildlife Refuge/OR/Coquille River estuary (2007-2013, Silver et al. 2017)