Before the coming of the pioneers, the prairies of Illinois provided habitats for hundreds of species of animals. Some of the large mammals, such as the bison and elk, disappeared in the early nineteenth century, but we can still find many of these mammals, birds, reptiles, and insects today.
The American Bison (Bison bison) was found throughout the prairie in the early 1700s, but decreased sharply in the late 1700s because of severe winters and heavy hunting with rifles. Native Americans hunted the bison for food and clothing. It was probably extirpated from Illinois by 1830. It grazed on prairie grasses, traveling in herds between summer and winter ranges, which were sometimes a distance of 400 miles apart.
The bulls may weigh up to 3,000 pounds. The smaller land slimmer cows weigh up to 900 pounds. Bison are capable of running at a top speed of 35 miles per hour. Their average life span is about 25 years. Cows usually give birth to a single calf in May.
Franklin's ground squirrel (Spermophilus franklinii) occurs in the tall grass prairie regions of Illinois. It lives in well-drained burrows, where it hibernates in winter. It is omnivorous, feeding on a variety of plants and carrion (dead animals), other small mammal material, insects, bird eggs, and ground-dwelling birds. Four to eleven young are born in the fall.
Dickcissel (Spiza americana) is a common migrant and summer resident in grasslands. It feeds mostly on seeds. The female lays three to five blue eggs in a bulky crude nest on the ground or up to two meters high in weeds or small trees in mid-May to early August.
Prairie Chickens forage on the ground for insects, especially grasshoppers. They also eat a variety of plant material, including leaves, buds, seeds, and acorns. Females lay seven to seventeen eggs in a nest on the ground among grasses and weeds.
The scientific name refers to the Prairie chicken's mating habit of "booming"
by filling their air sacs as they perform their mating ritual.
Learn more about this at DNR
Brown-headed cowbird (Molothrus ater) got its common name from its habit of following the bison heard on the short-grass prairies and eating the insects stirred up by the bisons' hooves. When European settlers opened up more land to short crops, the cowbirds came into this habitat. This also exposed other species of birds to the cowbirds "brood parasitism" - its habit of laying eggs (about seven, one at a time) in the nests of other species of birds, not building their own nests.
The cowbird is a common migrant and summer resident in grasslands with low, scattered trees. It feeds on seeds and insects.
American goldfinch (Carduelis tristis) is a common summer and winter resident and migrant, found in a variety of habitats. It feeds mostly on seeds, but feeds its young mostly insects. The female lays five to six eggs in a nest lined with thistle down in weedy shrubby areas, usually in a small tree.
Learn about more prairie birds.
Learn about other prairie reptiles.
Invertebrates (Insects and spiders):
Black and yellow argiope spider (Argiope aurantia) constructs its large orb web in fields, marshy places, and meadows. It is found throughout the United States. The mature adults trap and feed on mostly grasshoppers. On the web can often be found an egg sac the size of a hickory nut. It is constructed in the fall. Eggs hatch in the spring.
American grasshopper (Schistocerca Americana) occurs in a variety
of habitats in the southern and Midwestern United States. It feeds on a wide
variety of plants. The female lays clusters of 60 to 80 eggs in the spring
and again in the fall. This species is one of only a few grasshoppers that
overwinter as an adult.
Handsome locust (Syrbula admirabilis) occurs in grasslands and wet meadows of Illinois. It feeds mostly on prairie grasses, especially big bluestem. Eggs are laid in the soil in the fall to hatch in the late spring.
Monarch butterfly (Danaus plexippus) is a common butterfly in open areas throughout Illinois. Its caterpillar feeds on milkweed (Asclepias sp) species, some of which contain a poison that is absorbed by the caterpillar and that makes the adult unpalatable to prey. Monarchs migrate as far south as Mexico to overwinter. Females lay eggs on the way north in the spring.
Learn about other prairie
Learn more about prairie animals at the Museum's Prairie Web module