Lake Ilo and smaller wetlands are the main attraction for wildlife to this Refuge. Lake Ilo is 1,240 acres in size with a maximum depth of 15 feet. A 145 acre marsh, Lee Paul Slough, is attached to Lake Ilo by a canal. The slough provides a location to view marsh animals and plants.
Another two dozen smaller wetlands make up the remaining Refuge wetland habitat. Waterfowl, shorebirds, and other wildlife species find the wetlands attractive as summer breeding habitat and as a spring and fall migration stop. Water development and management has made Lake Ilo NWR a very important resource for wildlife and people.
Refuge uplands, amounting to 2,650 acres, are composed of native prairie, introduced grasses, cropland, and tree plantings. Refuge management is directed at preserving native plants and animals and creating as much species diversity as possible. Careful use of prescribed fire, grazing, haying, and rest periods are all tools used to stimulate this process. Native grasses and forbs are planted in former croplands to reestablish a grassland community. Approximately 50 acres of cropland remain in cultivation for wildlife food on a partnership basis with neighboring farmers or by Refuge staff.