Order Rodentia - Family Sciuridae Author Wilson, Don E. Author Reeder, DeeAnn text 2005 The Johns Hopkins University Press Baltimore Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2 754 818 book chapter 0-8018-8221-4 10.5281/zenodo.7316535 Sciurus (Hesperosciurus) griseus Ord 1818 Sciurus (Hesperosciurus) griseus Ord 1818 , J. Phys. Chim. Hist. Nat. Arts Paris, 87: 152 . Type Locality: "The Dalles of the Columbia" [River, Wasco Co., Oregon , USA ]. Vernacular Names: Western Gray Squirrel . Subspecies: : Subspecies Sciurus (Hesperosciurus) griseus subsp. griseus Ord 1818 Subspecies Sciurus (Hesperosciurus) griseus subsp. anthonyi Mearns 1897 Subspecies Sciurus (Hesperosciurus) griseus subsp. nigripes Bryant 1889 Distribution: C Washington , W Oregon , and California ( USA ) to Baja California Norte ( Mexico ). Conservation: IUCN – Lower Risk (lc). Discussion: Subgenus Hesperosciurus ( Hall, 1981:433 ) . Reviewed by Carraway and Verts (1994 , Mammalian Species No. 474).