18 CONDITION OF ELK IN JACKSON HOLE, WYOMING. 
mild winten and in times of plentiful food supply, many of the older 
animals of both sexes die. Owing to the fact that a large proportion 
of the animals killed for food during the autumn months are females, 
I great many young calves are left motherless and are in a more or 
weakened condition when winter comes on. Furthermore, 
many of the late-born calves are poorly equipped to withstand the 
winter, and this is likely to be true also of many of the cows which 
have borne and nursed young the previous season. 
A conservative estimate places the number of elk which died of 
starvation in the Jackson Hole region during the winter of 1910- 
II at some 2,000 to 2,500. Of these, by far the greater number 
were calves of the previous year. Probably 75 per cent of the 
calves which came into the valley in November and December had 
perished of starvation before the end of the following March. In 
some bends the loss of calves was as high as 90 per cent, but other 
bands suffered less. The greater part of the loss occurred before 
feeding began, but large numbers, both calves and older animals, 
were so weak that they died even when receiving what would ordi- 
narily have been an abundance of food. Many, in fact, on being fed 
after a period of starvation, die almost immediately. There is 
evidently little difference in the relative mortality of the sexes in 
adult elk, find out of 75 calves examined for sex 32 were males and 
43 were females, indicating that in the case of the young the burden 
on the sexes is not strikingly unequal. 
HABITS IX SPRING AND EARLY SUMMER. 
As spring advances and the sides of hills bordering the valley 
become bare, the elk, especially the older animals, leave their haunts 
in the lower part of the valley and seek the hillsides, where they 
subsist on the dry grass which has been exposed by the melting of 
the snow. At the time of my arrival, about the middle of March, 
they had already begun to work back into the hills, and the numbers 
being fed were much less than originally. Many of the animals at 
this season spend a part of their time on the hillsides, visiting the 
feeding grounds at the time when they have been accustomed to be 
led. As the spring advances, this movement into the hills becomes 
more and more pronounced, until the valley is entirely deserted. 
The last ones left that part of Jackson Hole south of the Gros Ventre 
Buttes, known locally as South Park, about April 26, some time after 
feeding of hay had been discontinued. They were subsisting on 
the green grass then springing up on the borders of some. spring-fed 
'•reck-. They were -ecu on the adjacent hillsides until early May. 
In the swamn north of Jackson a Urge herd remained later. Inves- 
iou showed that they were feeding on the green leaves of the 
