According to Wikipedia “Unlike most other deer species, moose do not form herds and are solitary animals, aside from calves who remain with their mother until the cow begins estrus (typically at 18 months after birth of the calf), at which point the cow chases away young bulls. Although generally slow-moving and sedentary, moose can become aggressive and move quickly if angered or startled. Their mating season in the autumn features energetic fights between males competing for a female.”
Contrary to this, over the years I’ve learned that moose do gather in herds. The easiest place to view this is around Blacktail Butte in Grand Teton National Park. Fall and early winter are the prime viewing season. The moose group in far greater numbers, perhaps because of mating season. The bulls still have antlers too, they wont fall off until later this winter.