During the peak period of growth in the summer, antlers may grow one inch per day. Calving occurs in late May and early June. Most elk on the refuge are 3-10 years old. Seasons of Elk During Autumn males gather harems of females that they mate and zealously guard. Bugling is a male dominance display that attracts females and states the rank of the male.
Rival males respond by bugling back.
Bulls may actually spar with challengers, after first demonstrating threat postures, then thrashing the ground with their antlers. A large percentage of the cow elk become pregnant each year. The rut is an intense time for bulls. Dominant males expend a considerable amount of energy. The price for passing on their genes consists of entering winter with weight loss and in some instances a depleted physical condition.