Three quarters of the site's perimeter is Rend Lake shoreline. This varied topography provides excellent habitat for a variety of upland and woodland wildlife, as well as waterfowl, shorebirds and raptors. Birders visiting the area have an excellent chance of seeing great blue heron, American bald eagle, red-tailed hawk, and a variety of shorebirds and waterfowl. The resident population of ring-necked pheasant that Wayne Fitzgerrell supports is unique in southern Illinois. White-tailed deer, raccoon, opossum and squirrel are among the mammals wildlife enthusiasts are likely to see.
Anglers visit the site to fish for crappie, white bass, largemouth bass, and channel catfish.
An aggressive fisheries management program, which includes annual stockings of sport species, helps cement Rend Lake's reputation as one of southern Illinois' most popular fishing spots. Newly constructed lodging and restaurant facilities further enhance the site's reputation as a recreational site offering something for every member of the family. Since 75 percent of the park's boundary is shoreline, the site provides outstanding bank fishing opportunities. Rend Lake is well known as an outstanding sport fishery for white and black crappie, particularly in the early spring, as well as excellent fishing for largemouth bass, channel catfish, and bluegill. As a result of a Natural Resource Department stocking program, the lake is one of the few southern Illinois locations to have a noteworthy white bass fishery.