Eastern Pipistrelle, Pipistrellus suhflavus. The east- 

 em pipistrelle is a small bat with fur that is orangish-tan 

 at the tips and black at the base. The yellow-orange 

 forearm and contrasting blackish wing membranes 

 make it easy to identify. Referred to as "pips," these 

 common, '/5-ounce animals are the smallest Illinois 

 bat. They range throughout Illinois during the summer, 

 but only a single pip has been reported from the Chi- 

 cago area and very few from other northern portions of 

 the state. In winter, when their movement is restricted, 

 at least one pip is commonly found in almost any cave 

 or mine in Illinois. 



black (charcoal gray) basal portions with cinnamon or 

 chestnut tips. Often confused with the little brown bat 

 it may be distinguished by a keel-like projection from 

 its kalcar (heel bone). The Indiana bat can be found in 

 almost any county in Illinois during summer. It in- 

 habits upland and floodplain forests interspersed with 

 openings that are usually near waterways. These bats 

 are known from very few caves and abandoned mines 

 in Illinois but may form dense clusters of up to 300 bats 

 per square foot when they hibernate on cave ceilings. 



Females establish nursery colonies of up to 100 

 adults beneath the bark or in the hollow portions of 



Hibernating cluster of the little brown bat « 1952 j l upofe rue Nanonai Auouboo soc«iy conecnor pr 



Females occur singly or band together in small 

 numbers during summer, when they produce their two 

 pups. Summer roosts are virtually unknown but prob- 

 ably occur among the foliage of trees, in tree hollows, 

 or beneath the bark. Pips are rarely found in buildings, 

 but their small size and inconspicuous habits make 

 them difficult to spot. 



Indiana Bat, Myotis sodalis. Named for the state 



where it was first described, the medium-sized Indiana 



12 bat weighs only '/4 ounce and has bi-colored fur — dull 



dead trees. Aided by the U.S. Fish and Wildlife Serv- 

 ice, the Indiana Bat Recovery Team, and several coop- 

 erating state agencies, Illinois was the first state to 

 gather comprehensive information on roost site selec- 

 tion, movements, home range, and activity of Indiana 

 bats. Tiny transmitters, weighing V32 ounce, were 

 glued to the backs of the bats, and their movements 

 monitored intensively. Summertime radiotracking 

 studies identified 45 trees throughout Illinois that were 

 used as roosting sites. 



