Illinois Chorus Frog

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Illinois Chorus Frog

Illinois chorus frog
Pseudacris illinoensis
Hylidae (treefrogs and allies) in the order Anura (frogs)

Tan to tannish gray with a white belly and many dark brown or gray irregularly shaped markings on its body. This frog has a distinguished V-shaped marking between the eyes, a dark stripe from snout to shoulder, and a dark spot below each eye. Young froglets are dull gray and have inconspicuous body markings. The skin of the Illinois chorus frog has a rough texture. The large and muscular forearms of this frog are used to dig the burrows where it spends much of the year. The webbing on the hind feet is poorly developed.

Body length: 1 to 1½ inches.
Habitat and conservation: 
Sandy grasslands, wetlands, and agricultural areas of the Bootheel. Habitat changes resulting from channelization, filling of wetlands, conversion of sand prairie to agricultural fields, and highway construction were reasons for the original concern and candidate status of this reclusive frog. Management efforts should be focused on creating sand prairie grassland habitat or improving existing areas.
The tadpoles eat suspended matter, organic debris, algae, and plant tissue. The adult frogs eat small insects and burrowing insect larvae.
Distribution in Missouri: 
Historically, the Illinois chorus frog occurred throughout sandy grasslands in southeastern Missouri. Its present range includes isolated populations associated with specific soil types in Mississippi, Scott, Dunklin, and New Madrid counties.
Listed as imperiled by the Missouri Department of Conservation and is currently a candidate for federal listing by the U.S. Fish and Wildlife Service. It occurs only in parts of Illinois, the Missouri Bootheel, and one county in extreme northeastern Arkansas. Formerly considered a subspecies of the Strecker’s chorus frog, in 2004 the Illinois chorus frog was given full species status.
Life cycle: 
This secretive frog emerges from its burrow to breed in late winter, then again to feed during summer rains. Courtship begins in February and may continue into early April. Frogs are stimulated to migrate between burrowing areas and breeding pools when heavy rains occur, and temperatures exceed 48 degrees Fahrenheit. The males’ breeding call is a series of high-pitched, rapid, birdlike whistles. Females lay numerous clusters of eggs. Tadpoles develop into subadult frogs by May or June.
Human connections: 
Agricultural development in the Bootheel has destroyed nearly all the natural ephemeral pools where this species formerly bred, and housing development has nearly eliminated the sand prairie. This frog still lives in some highly cultivated areas but may not survive continued habitat destruction.
Ecosystem connections: 
Ecosystems have been likened to jets, and species as the plane’s components. If a species of gnat, violet, or frog disappears, it might be like losing a rivet from a wing. A few missing rivets may not affect the jet’s safety — but at some point, if enough components disappear, it will crash.
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