DEER 239 



Coyotes, especially the big Mountain Coyotes, occasionally 'pull down' 

 fawns or sickly adults. If caught in snow more than 18 inches deep, even 

 adult and able-bodied deer are apt to be run down by these predators. 

 The coyotes run easily on the top crust of the snow, but the deer break 

 through and flounder helplessly in the deeper drifts. In the Yosemite 

 region, however, the chief wild enemy of the Mule Deer is the Mountain 

 Lion. The way in which lions capture deer is described in another chapter 

 (p. 97), where also the numbers probably killed each year are estimated. 



The interrelation of Mountain Lion and Deer has naturally become an 

 important subject of discussion and concern among sportsmen, to whom 

 a deer is something to be sought after, both for its flesh and as a trophy. 

 In a very definite sense the Mountain Lion is, in territory open for hunt- 

 ing, the sportsman's rival; hence, from the sportsman's standpoint, the 

 lion should be eliminated. But in the Yosemite National Park, where the 

 aim is to preserve free from human interference all the animal life, it is 

 the hunter who is eliminated, and so the situation is altogether different. 



The close grazing of cattle in the territory to the west of the Park, 

 which is comprised in the wintering grounds of a good proportion of the 

 Yosemite deer population, has inevitably reduced, especially in hard years, 

 the number of deer which can be carried over there through the winter. 

 Not only the grasses, but most especially certain thin-leafed kinds of 

 deer brush, have been browsed down by cattle and goats to mere vestiges 

 of their former quantity ; and the deer are hard put to it when the snow 

 lies far down on the west Sierran slopes. In last analysis, counting out 

 man, the important factor in the reduction of the numbers of deer is the 

 reduction in the quantity of food available to them at the most critical time 

 of the year, rather than the levy upon their numbers by lions. 



Except as the factor of hunting and poaching in the territory along the 

 western edge of the Park also affects the deer population of the Yosemite, 

 we do not see that the permanent existence, in relatively normal numbers, 

 of Mountain Lions within the area in question can be expected to reduce 

 the total population of the deer which will be maintained from year to 

 year. In other words, if the Yosemite Park is administered as a true 

 'refuge' for its animal as well as its plant life, then primitive conditions 

 should be maintained absolutely, to the end that all the constituent species 

 persist in the same relative numbers as they did in early times. The 

 maximum numbers of any and all herbivores which can exist will be 

 determined by the amount of plant food available at the season of least 

 supply ; and the numbers of carnivores which can exist will be determined 

 by the amount of animal food available to them at the season of scantiest 

 supply. 



