The Shumaker unit is 13,415 acres located in Asotin County, 30 miles south of the town of Asotin. The eastern border is less than a mile from the Snake River and most of the unit is adjacent to either the Grande Ronde River or Joseph Creek. Elevations range from 825 feet along Joseph Creek up to 4,913 feet at Mt. Wilson, the highest point in the vicinity. The first acquisition was in 1974 for enhancing bighorn sheep, mule deer, and upland game bird populations. Since then, bighorn sheep have been reintroduced, along with turkey and pheasant. Large populations of California quail exist, along with blue and ruffed grouse, Hungarian partridge, and chukar. Over 100 species of birds have been identified, including a remnant population of mountain quail. Horseback riders, hikers, and bird watchers commonly make use of trails. Joseph Creek is the lowest tributary of the Grande Ronde River, and roughly 2.3 miles of Joseph Creek and 8 miles of the Grande Ronde run through or adjacent to the wildlife area. Both of these drainages provide habitat for Chinook salmon, summer steelhead and bull trout, although high temperatures affect water quality and may influence fish presence, particularly bull trout.