MIDDLE ILLINOIS RIVER

Historically, the Illinois River Valley has been one of the most important migration areas for waterfowl in North America. During spring and fall migrations, waterfowl are attracted to the abundance of food available in the shallow bottomland lakes, sloughs, marshes, ponds, and forests. Early accounts of the area describe vast numbers of waterfowl. The Illinois River Valley has been greatly altered by drainage of the wetlands and sedimentation of the river. Aquatic vegetation has disappeared from the lakes and the numbers of some waterfowl species began to decline in the 1950s.

SIZE: 575,515 acres; 899 square miles

LOCATION: Central Illinois, the Illinsoi River from Peoria to Florence; Brown, Cass, Fulton, Mason, Morgan, Pike, Peoria, Schuyler, Scott, and Tazewell counties.

The Middle Illinois River RRA incorporates floodplain and upland landscapes along the Illinois River from just below Peoria to Florence. The Middle Illinois River site is the third largest of the RRAs. The boundary was modified for this site to include watersheds with sand prairies. Significant amounts of state land occur in this RRA.

The plant communities of the sand prairies are a mix of native tallgrass species and plants more commonly associated with the western U.S. The sand deposited by glacial meltwaters favors survival of plants that can tolerate dry and sometimes shifting environments. One such plant is the prickly pear cactus. This native cactus is found in several habitats in Illinois, but is most abundant in sand prairies.

The Illinois chorus frog is restricted to sandy floodplains, and the sand prairies adjacent to the Illinois River provide ideal habitat. In Illinois, this frog is found exclusively in three widely separated regions. A state-threatened species, it is dependent on the protection of its habitat. The chorus frog has the unusual habit of burrowing into the sand with its front feet (the vast majority of frogs use their hind feet). It also feeds underground, a behavior unknown in any other frog species. The Illinois chorus frog can only be seen in the spring, when it comes out of the ground to mate.

LANDCOVER: Cropland is the predominant land cover, accounting for half the land area in this RRA. Approximately 22% of the Middle Illinois River RRA is either upland or bottomland woods. This site has the third highest acreages of nonforested wetlands and bottomland forest.

NATURAL AREAS : Thirty-eight Natural Area sites are located in the RRA, totalling the sixth highest percentage of natural area acreage among the RRAs. Prominant natural features include sand prairies, hill prairies, springs, seeps, savannas, ponds, lakes, woods, and habitats for herons, eagles, and the Illinois Mud Turtle. Forty-three percent of the total acreage occurs at Meredosia Refuge Natural Area.

BIOLOGICALLY SIGNIFICANT STREAMS : There are no BSS streams within this RRA.

HERITAGE SITES : There are 134 Heritage sites within this RRA. Nine significant community types, 19 plant species, 22 animal species occur here. Three large forest tracts and three rookeries are located in this RRA.

STATE AND FEDERAL LAND : Approximately 9% (53,129 acres) of the RRA is in state (5.5%) or federal (3.7%) ownership. This site ranks first for acreage in state ownership. There are nine state holdings--one state park, five conservation areas, one forest, and two fish and wildlife areas. Emiquon, Chautauqua and Meridosia National Wildlife Refuges are federal lands located here.

NATURE PRESERVES : The six Nature Preserves located in the Middle Illinois River RRA protect sand prairie, hill prairie, wet prairie, and savanna communities. The largest is the Sand Prairie-Scrub Oak Nature Preserve, an approximately 1,400 acre site of sand prairie, sand savanna, and sand forest.

NATURAL DIVISIONS : The site encompasses five natural divisions. Most of the RRA is comprised of the Upper Mississippi and Illinois River Bottomlands (42%), Illinois and Mississippi River Sand Areas (26%), and Western Forest-Prairie (24%) Divisions.