THIRTY-FIFTH BIENNIAL REPORT 43 



were the same as those relative to Rocky Mountain mule deer, namely ; 

 actual census work, information on numbers, sex ratio, condition of the 

 deer herd, disease outbreaks and range conditions. Much definite and 

 practical information has been gathered from these studies. 



The southern California studies gave much information that the 

 Division needed. Some of the more interesting facts determined were 

 those relative to population per square mile, sex ratio, food conditions 

 and migration. 



In the Rocky IMountain mule deer region of northeastern Cali- 

 fornia, the following tabulation covers a period of four years of fall 

 and winter observation: 



1^. ~'' Si's m"? »! 2o*',-oi>520r».2 



*: ic 



O •'H' o 



o| ?s 'S.^ 



&1^ &1^ ftJrO 





1933-34 9,263 1,449 143 7,814 5,690 2,124 1-3.9 1-1.4 2.6-1 



1934-35 26,473 4,172 207 22,301 14,885 7.416 1-3.5 1-1.8 2-1 



1935-36 8,928 1,353 125 7,575 5,361 2,214 1-3.9 1-1.6 2.4-1 



1936-37 21.517 3,904 147 17,613 13,652 3,961 1-3.5 1-1.0 3.4-1 



Foiir-yeai* 



summary 66.181 10,918 622 55,308 39,588 15,715 1-3.62 1-1.44 2.52-1 



It will be noted in the above tabulation that there was a total of 

 622 spike bucks. Most of these were observed in the Fall River-Burney 

 Region and in eastern Siskiyou County where there has been consider- 

 able mixing between Columliian black-tailed deer and Rocky ]\Iountain 

 mule deer. Even when mixed and remixed many times, the yearling 

 bucks with any black-tail blood generally are spikes rather than forked 

 horns. Normally, about one full-blooded Rocky Mountain mule deer 

 yearling buck out of fifty is a spike. About one out of ten is a three- 

 pointer and very rarely a four-pointer. 



1937 and 1938 were very good years producing an al)undance of 

 deer feed on the deer ranges of the State. The average growth on 

 bitter brush or antelope brush PiirsJiia iridenfala in nortlieastern Cali- 

 fornia during 1937 was about 2^ inches and slightly more in 1938. 

 Other food plants made a good growth and provided an abundance of 

 forage and browse. 



The reduction or elimination of sheep and substitution of cattle on 

 some parts of the mule deer range has augmented the carrying capacity 

 of this range. 



In southern California particular studies were made bordering 

 the two refuges, 4-A in San Bernardino County and 4-B in Los Angeles 

 and San Bernardino counties. California mule deer in areas adjacent 

 to Refuge 4-A averaged about 6 per square mile and the same sub- 

 species adjacent to Refuge 4-B averaged about 6.5 per square mile. 

 Areas within Refu2e 4-A averaged about 9.3 per square mile and in 

 Refuge 4-B about 9.8 per square mile. 



Two areas adjacent to Refuge 4-E in San Diego County averaged 

 5.3 southern mule deer per square mile and two areas within the same 

 refuge averaged 5.8 per square mile. 



One area adjacent to Refuge 4-G in Riverside County averaged 

 16.2 deer per square mile and in the refuge averaged 14.3. 



An estimate of the total range of the six subspecies of deer com- 

 monly found in California has been made. There are 155,652 square 



