52 CALIFORNIA FISH AND GAME 



MULE DEER STUDY PROGRAM 



By James Moffitt 



The Division of Fish and Game lias received numerous reports in 

 the past two or three years from its game wardens, sportsmen, game 

 conservationists and U. S. Forest Service employees purporting a 

 decline in tlie numbers of mule deer inhabiting the northeastei'n por- 

 tion of the State. Deer kill statistics indicate a reduced kill in this 

 area in the past two seasons, which, as discussed beyond, may indicate 

 deer depletion in this section. The Division has investigated the matter 

 and is of the opinion that some reduction, although not an alarming one, 

 has occurred among these deer in recent years. It now desires to 

 ascertain the reasons for the depletion in order that remedial measures 

 may be undertaken. 



Before proceeding with an explanation of the mule deer study 

 program, by which means it is intended to procure the information 

 needed, it seems desirable to indicate in more detail than has liereto- 

 fore been done the range of mule deer in this section, to review the 

 status of these deer in the past and the kill statistics for the area, to 

 recount the increasingly restrictive game laws enacted in recent years 

 and to speculate upon some of the probable reasons for the recent 

 depletion. 



The species concerned is the Rocky Mountain mule deer, Odorm- 

 leus hemionus hemionus, which California hunters often term the 

 "Modoc" mule deer in distinction from the smaller California mule 

 deer {O.h. calif ornicus) of southern California. This is the common 

 deer of Modoc County and it is also plentiful in most parts of Lassen 

 County, the eastern half of Siskiyou County and in extreme eastern 

 Plumas, Sierra and Nevada counties (see Fig. 15). South of Placer 

 County, where this deer is of rare occurrence, its status is not well 

 known but a few individuals undoubtedly enter California in suuhium- 

 along the eastern border south to j\Iono County, where the present 

 species is thought to meet the range of the newly described Inyo mule 

 deer {O.h. inyoensis), (see California Fish and Game, vol. 19, 1938, 

 p. 274). Therefore, the vast majority of the Rocky Mountain mule 

 deer's range in the State is included in the area under consideration, 

 which, for convenience, will be termed the "Modoc" region. 



The accompanying map (Fig. 15) indicates as nearly as the writer 

 has been able to ascertain, the average summer range of the Rocky 

 Mountain mule deer in California. Some few individuals may. in 

 summer, stray west of the north and south line drawn through Shasta 

 Valley, but the bulk of the mule deer in this section doubtless stop their 

 westward spring migration at this valley's eastern edge. Similarly, 

 further south, occasional mule deer may be noted west of the boundary 

 line indicated ; but it is believed that in general this line marks the 

 western range of this deer. Columbian black-tailed deer {Odocoileus 

 columbianus columhianus) frequently occur east of this line, in fact 

 they do so commonly and regularly at many points. This is especially 



