Both bulls and cows are strong swimmers. Natural enemies of elk include wolves and cougars. Bears and coyotes kill some calves and sick adults. Many of the larger elk herds in the U.S. and Canada are overpopulated. Sometimes there's not enough food to the big herds.
Some elk get sick and die.
Here are a few more websites devoted to elk. This extensive site contains a wealth of inforomation about elk and their habits and links to two other good articles on elk by the author. Learn facts about the location, behavior, diet, and physical characteristics of these large members of the deer family. Includes lots of elk facts.