acologic types and takes accoant of all observable mammals and birds as well as 

 the principal plants in the area concerned. Attention is given to soils , and 

 estimates are made of ecologic conditions essential for v#ildlife welfare during 

 the most critical, as well as during the most favorable, season of the year, 



Fischer, Davis, Iverson, and Cronemiller 3/ show how careful counting, 

 determination of ecological relationships, and ascertainment of movements have 

 resulted in a managanent plan for the herd of mule deer that migrates between 

 southern Oregon and northern California. Political boundaries, prejudices of 

 hunters, and complex administration may make the recommended remedies difficult 

 to apply, but wildlife research based on what might be called ecological life 

 histories has indicated what to do to obtain the best results. 



Obviously something more than general terras is needed when an analysis of 

 the types of vegetation used by mammals - perhaps more especially game mammals - 

 becomes necessary. Workers like Soulen 4/ and Barick (1945) are helping to 

 provide modern methods for analyzing habitat conditions, for example, of stream- 

 sides for beavers and forest edges for deer and other animals. 



In studying the food habits of the Texas beaver, Soulen devised a "beaver 

 site survey,** in the course of which detailed information was gathered on the 

 species of trees present, including the number of trees of each species and the 

 diameter and height of each (on an area one chain square), as well as similar 

 information on the species and heights of shrubs and the number of stems in 1 by 

 12 inch transects taken at 5,5-foot intervals in a straight line back from the 

 water's edge. He also counted the trees and shrubs per chain acre (an area one 

 chain wide and 10 chains long) , These details enabled him to express in quanti- 

 tative terms the particular features that made some sites more favorable for 

 beavers than others. 



While Barick*s (1945) analysis of forest edges does seem "formidably cumber- 

 some," nevertheless it points the way toward a more exact understanding of the 

 forest edges which are so important in game management. Itie habitat analysis, 

 associated with studies of the mammals and other forms of animals which dwell, 

 feed, and breed in the area concerned, throws new light on the community func- 

 tioning in which the mammal or other creature takes part. Such analyses cannot 

 be neglected in field studies directed toward the better understanding of 

 mammalian life histories. 



3/ Fischer, George A,; Davis, John C; Iverson, Floyd; and Cronemiller, 

 F. P. The winter range of the interstate deer herd, Modoc National Forest, 

 California. U, S. Dept. Agr., Forest Service Region 5 report, 20 pp., illus, 

 1944, [Processedj 



4/ Soulen, Garrett H. Food habits of the Texas beaver ( Castor canadensis 

 texanus) as related to the State restoration program. Unpublished thesis. 

 A. and ii. College of Texas, Library, College Station, Texas, 



8 



