228 CALIFORNIA FISH AND GAME 



believed to be deer that had only recently come down from the higher 

 mountains. At this time the meadows in Giant Forest were still free 

 from snow. Ninety-eight inches of snow was officially reported on the 

 ground on January 31, 1932, when all deer had migrated to lower 

 elevations in the oak belt. 



During seasons of normal snowfall some mule deer remain through- 

 out the year in Yosemite Valley and do not migrate at all. At this 

 elevation, 4000 feet, the snow usually does not reach a depth sufficient 

 to force deer to leave the Valley. However, during winters of heavy 

 snowfall, nearly all of the deer drift down the Merced River Canyon 

 to lower levels. According to the park superintendent's report of Feb- 

 ruary 3, 1932, "between January 30, and February 3, a total of 51 

 inches of snow fell on the floor of Yosemite Valley." This heavj^, wet 

 snow packed on top of 32 inches of snow already on the ground gave 

 a depth of 83 inches, which is the "greatest depth of snow recorded for 

 Yosemite since park weather records began in 1906." 



At my request. Assistant Postmaster Charles "W. Michael and Park 

 Naturalist C. A. Harwell made special investigations covering available 

 food supply, migration, and relation of predators to deer during this 

 critical period. Their findings are so inii)ortant that they are given 

 herewith in detail. In his letter of February 18, 1932, Michael states : 

 "During the big storm, at the end of January, or shortly after, most of 

 the deer went down the canyon. After the storm there was one deer 

 where there had been ten before. * * *" Continuing, he says: 

 "My morning walk takes me through the winter haunts of the deer, 

 about the mouth of Indian Canyon. Twice in the last week Mrs. 

 Michael and I have had an all-day trip. One trip to Mirror Lake and 

 one trip down the Valley as far as the bear pits. On the day we went 

 down the Valley, the only deer seen were three we found opposite the 

 post office on our return. On the day we went to Mirror Lake, three 

 deer were seen in Camp 15, feeding on fallen cedar boughs, and two 

 were seen on the edge of Tenaya Creek. Following is our daily count of 

 deer seen from February 9 to 17: 1—5—0—2—0—3—8—13." 



The 13 seen on February 17 were believed to represent all the deer 

 between the post office and the Ahwahnee grounds. Of these, probably 

 10 were deer that had come back up the canyon after the storm. 



Concerning the shortage of food supply as the cause of deer leaving 

 the Valley, Michael states: "Lack of food had nothing to do with the 

 deer exodus from the Valley. Never since I have been in the Valley has 

 there been so much available food. The storm brought down such a 

 litter of branches that the Valley is strewn from end to end with for- 

 age that has been acceptable to deer in other seasons. * * * Heavy 

 snows bring within reach much browse that is unreachable in fair 

 weather. With conditions as they are, there is no reason for deer to 

 go hungry. 



"In my opinion deer leave the Vallej' not from food shortage, 

 but because in heavy snows thej'' are at the mercy of their natural ene- 

 mies — coyotes, bobcats and mountain lions. Bobcats are more numerous 

 in the Valley this winter than they have been for years." 



Park Naturalist C. A. Harwell in his report accompanying letter 

 of February 16, 1932, gives evidence similar to the above report as 

 follows: "During the extremely heavy storms of the past few weeks 



