Invasion

Invasion Description

1st Record: Salem/OR/Willamette River (1893, Lampman 1946)

Geographic Extent

Salem/OR/Willamette River (1893, Lampman 1946; Hughes and Gammon 1987); Portland/OR/Willamette River (Farr and Ward1993); OR-WA/Columbia River (Chapman 1942; Lampman 1946); north of Clatskanie off hwy 30/OR/Clatskanie Slough (2001, USGS Nonindigenous Aquatic Species Program 2014); north of Knappa junction or Brownsmead junction off hwy 30/OR/Blind Slough, Columbia River (2001,USGS Nonindigenous Aquatic Species Program 2018); north of hwy 30, near Westport, 10 miles west of Clatskanie/OR/Westport Slough (2001, USGS Nonindigenous Aquatic Species Program 2018); 6 miles northeast of Clatskanie/OR/ Crims Island Slough (2001, Crims Island Slough (2001, USGS Nonindigenous Aquatic Species Program 2018); northwest of Columbia City off hwy 30 at Reichold Chemical (access only at south end)/OR/Deer Island Slough (2009, USGS Nonindigenous Aquatic Species Program 2018)