236 



CALIFORNIA FISH AND GAME 



BREEDING HABITS 



AGE AT WHICH BUCKS DEVELOP ANTLERS 



Under normal conditions in the central Sierra Nevada region, the 

 first antlers of male California mule deer are single spikes from three 

 to ten inches in length. Such antlers start to develop when the animal 

 is about one year old. However, in early faAvns the growth of the 

 antler is sometimes sufficient to perforate tlie skin the first season 

 (Caton, Antelope and Deer of America, 1877, p. 192). I have several 

 times verified this fact. In Yosemite on January 30, 1929, I observed 



,1*^ 



Fig. 7 8. After reaching: full physical development a mule deer buck besin.s to 

 decline. Although his antler.s retain their full spread a reduction in points takes 

 place as here shown. Yosemite, December fi, 1927. Mus. Vert. Zool. No. 5618. 



two male mule deer fawns in which antlers had just broken through 

 the skin on the tops of their heads. One had little sharp antlers not 

 over an inch long protruding through and above the surface of the skin. 

 Another male fawn had small antlers over one and one-fourth inches 

 in length. In both instances the diminutive antlers were hard and 

 free of velvet. At this date the majority of buck fawns gave no indi- 

 cation of their antlers coming through the skin at any time in the near 

 future. In both instances just cited the fawns stayed close to and were 

 dependent on their mothers. These fawns could not have been more 

 than eight months old at the date of observation. 



