Invasion

Invasion Description

1st Record: OR/Lower Willamette River; OR/Multnomah Channel at the lower end of Sauvies Island (Lower Willamette River) (Lampman 1946, Center for Aquatic Resource Studies 2003)

Geographic Extent

OR/Lower Willamette River; OR/Multnomah Channel at the lower end of Sauvies Island (Lower Willamette River) (Lampman 1946, Center for Aquatic Resource Studies 2003); Portland/OR/Lower Columbia Slough (Van Dyke et al. 2009, 2 specimens)