Predators are an important part of any ecosystem, including the world that elk inhabit. Humans are the primary predators of adult elk. They use weapons and must obey hunting laws and seasons that other predators don't follow. Black and grizzly bears usually eat plants, but they can easily grab calves less than three weeks old.
Grizzlies sometimes catch a full-grown elk.
Coyotes will kill calves if they can. But if an angry cow confronts them, they run away. An elk's flailing hooves can easily kill a coyote. Wolves used to be the primary predators of elk, but they are rare now in the United States. Where they do exist in the same area as elk, they continue to hunt in efficient groups that catch calves long after the young elk are capable of escaping bears.