Just a few weeks ago I found myself leaning out of an open car window in Yellowstone National Park to better watch a special spectacle. A large adult male wolf’s attack on a female elk backfired spectacularly. The wolf now ran for his life as the elk chased after the predator, down a steep slope, at 30 miles an hour.

Since then I have told many people about this turn of events in Yellowstone as it was one of the highlights of my trip. To my surprise most of my friends had no idea that among wild animals prey often attack predators. Healthy large prey such as elk, bison, and moose are too fast and strong for wolves to hunt, forcing the predators to instead attack mostly old, sick, and newborn individuals. Healthy prey animals can easily outrun wolves or turn on the predators and attack with their sharp hooves and antlers. Indeed, in my eight years of yearly wolf watching I have seen only three wolf hunts, all of which involved prey successfully chasing wolves.

A few days earlier during my trip I saw wolves feed on a moose carcass not far from the park road. Moose, just like elk, are common prey for wolves, and will similarly defend themselves when necessary. However, unlike elk, moose often react aggressively to the predator- like scent of dogs. Dogs are directly descended from wolves and still carry the wolf scent despite the huge physical and behavioral changes that dogs have undergone since their domestication.

This fact came into tragic focus on June 8, 2022, as an encounter between hikers and a moose resulted in serious injury to a hiker, minor injuries to another hiker and their dog, and the killing of the mother moose by local authorities. Although this encounter was particularly tragic, similar encounters between moose, dogs, and people happen yearly during the rut and calving season in my area.

Unlike wolves, dogs have neither the stamina or the speed to escape moose, so they often return to their owners when threatened. Unfortunately, an aggressive moose will often follow the dog, endangering both the dog and the human. Wildlife safety professionals agree that by keeping your dog on leash you can prevent your dog from getting close to a moose and leading the moose back to you, greatly reducing the risk for all individuals involved!

Moose are not the only animals who react aggressively to dogs; bears and coyotes are two other well known examples of species that will act aggressively around dogs. Humans are neither prey nor a threat to local species, but dogs have a long evolutionary history with many of the animals here in the Rocky Mountains. We can reduce our impact on the local wildlife by choosing to use extra caution and by keeping dogs on leash when walking our four-legged friends in areas inhabited by Colorado’s incredible wildlife.

Stay safe and enjoy the beautiful spring!