BIRTH OF YOUNG. 19 



coarse marsh grass, evidently the plants which had grown in autumn 

 after hay harvest. This grass had been kept green and succulent 

 by its covering of ice and snow. In early May the icy flooring which 

 had remained solid beneath the tangled grassy covering no longer 

 held up the animals, and they all left about May 10. For some time 

 longer upward of 100 remained on the East Gros Ventre Butte, 

 several hundred feet higher than the valley level. Here they lived 

 on the grasses and herbaceous plants which were fast springing up. 

 These elk remained here until about May 25, and then part or all of 

 them crossed westward and joined others on the larger West Gros 

 Ventre Butte, which afforded them more protection. Upward of 

 100 were seen there as late as May 31, and a few remained all summer. 

 Some of the older bulls dropped their antlers about March 25, 

 but the shedding continued for several weeks. Among a herd seen 

 May 4 were a number of bulls still bearing horns, but by May 15 

 even the younger bulls had all dropped them. As the shedding of 

 antlers is dependent on the general condition of the animal, the proc- 

 ess was delayed by the severe winter and late spring. In an earlier 

 spring following a normal winter the new horns are already well 

 grown in May, but in 1911 that month found most of the bulls with 

 their horns scarcely started, and in mid-August many were still in 

 the velvet. 



BIRTH OF YOUNG. 



About 75 per cent of elk cows over 2 years old bear young. The 

 majority of calves are born between the 25th of May and the middle 

 of June. Nearly all the testimony obtained on the subject is to the 

 effect that only one calf is born at a time. A few thought that twins 

 sometimes occur, but it seems probable that this opinion arose from 

 the fact that a cow elk is frequently followed by two calves during 

 the summer, the extra one being the deserted or orphaned offspring 

 of another cow. Many of the hunters had examined large numbers 

 of female elk with calf, and none of these ever found more than one 

 fetus. The proportion of the sexes at birth is nearly even. Large 

 numbers of the cows have their young in the hills in the vicinity of 

 Jackson Hole, but probably the majority of the animals which 

 come from north of Buffalo Fork return there before dropping their 

 young. This varies according to the season, an early spring allow- 

 ing a greater proportion to move northward before calving. The 

 young are usually born in a thicket, very often among aspens, and 

 are carefully concealed by the mothers when they have occasion to 

 leave them. The calves are said to begin to graze at the age of 4 to 

 6 weeks, and many are weaned in September. In some cases, how- 

 ever, weaning does not occur until October, November, or even 

 later. 



