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ILLINOIS NATURAL HISTORY SURVEY MANUAL 4 



Recognizable trails may be classified as high trails, runways, 

 or slides. There are often no sharp distinctions between these 

 three types, and some trails are difficult to assign to any one type. 



High trails are open paths, usually without canopies of grasses 

 or bushes, and they usually belong to relatively large animals. 

 Bison trails and deer paths are of this type and formerly were 

 common in the Illinois area. Present-day mammals making high 

 trails are red foxes, fig. 13, rabbits, woodchucks, and coyotes. 



Fig. 12. — Burrow and runways of muskrat. 



Runways are tunnels or small trails that often are so low 

 that the grass must be parted or the debris scraped away if 

 they are to be discerned by human beings. Although they are 

 not often seen, runways are abundant in both wooded and grassy 

 areas. They may be classified as those that are on the surface 

 of the ground, fig. 14, and those that are just under the sur- 

 face. Many runways that appear to begin on the surface dis- 

 appear below the surface and then reappear, forming a compli- 

 cated maze. Surface runways are much the same for a dozen 

 or more kinds of shrews, voles, and other mice, but the habitat 

 may provide clues for identifying the species that use them. For 

 example, runways in the debris of a forest floor are usually 



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