In a general study of the Pacific Northwest, the mean prey size of spotted owls was stated at 91 grams and were estimated to be about 34% higher than the mean prey mass of barred owls, but in a study specifically in the eastern Cascade mountains, where the barred appeared to more readily access large prey like snowshoe hares as well as flying and other squirrels, the barred owl’s mean prey size were contrarily 21% higher than the spotted owls in the mountains.