Did the sign say Roosevelt's elk? ISIS lists them as having Rocky Mountain elk which would make more sense as the Roosevelt's subspecies is restricted to the Pacific northwest. Seen too many Roosevelt's elks up there in your neck of the woods, you have them on the brain .
Although according to Geist these are not actual subspecies, but merely ecotypes. All North American wapiti and those found in eastern Siberia are of the same subspecies canadensis.