8 'LLINOIS NATURAL HISTORY SURVEY MANUAL 4 



HOW TO STUDY MAMMALS 



Mammals may be studied alive or as preserved specimens. 



Studying Live Mammals. — Live mammals may be studied 

 (1) directly, in the field or in captivity, and (2) indirectly, by 

 means of their signs — homes, trails or runways, tracks, drop- 

 pings, and food fragments or remains. Both types of observa- 

 tions are of importance in contributing to an understanding of 

 the habits of the animals. 



To study mammals in their normal activities in the field, one 

 must approach them slowly and inconspicuously, remain hidden 

 in a spot to which they come, or attract them by artifice. One 

 can sometimes attract mammals by placing baits at strategic 

 spots or by making imitative calls. For example, an appropriate 

 squeaking sound will sometimes bring an inquisitive chipmunk 

 within range for easy observation. At night one can follow the 

 activity of some mammals in the beam of a flashlight or in the 

 light of a gasoline lantern. 



One good method of studying small mammals and their life 

 histories is as follows: Select a plot of grass or woodland in 

 which mammals are present and mark it into quadrats; make 

 a record on cross-section paper of the runways, nests, and feed- 

 ing stations as they occur in each quadrat; keep notes on the 

 number of individuals living on the plot, time of activity, pres- 

 ence and development of young in the nests, and any other items 

 you may notice. Ground squirrels, chipmunks, and voles are par- 

 ticularly amenable to such observation. 



Another method of studying mammals is to observe them in 

 captivity. Care should be taken to provide quarters that are 

 suitable for the animals and for ease of observation. For some 

 of the shy and nocturnal mammals this type of study may be 

 one of the most efficient ways of obtaining accurate information 

 on breeding, rearing of young, food preferences, and behavior 

 characteristics. The animals can be caught in live traps, of 

 which there are many kinds to be purchased or made, set near 

 runways or nesting sites. Mice or shrews may be trapped 

 in a gallon can or other steep-sided container that has been sunk 

 in the ground flush with a runway. Some mammals that live 

 under logs or other objects on the ground can be captured by 

 raising the objects and seizing the animals before they dash 

 away. 



