Outdoors

Elk, Wolves and Lions

The forces that control elk populations are varied and complex

Lions kill more elk than wolves. At least that’s what a new study by Idaho Fish and Game, with implications for the entire Northern Rockies, suggests.

Well, that solves it. Wolves aren’t the problem after all.

If only wildlife management was that simple. If it was, we’d easily find solutions to the problems that perplex wildlife managers. And once they fixed all these easily solved problems, those biologists would soon find themselves out of a job, having fixed everything we’d hired them for in the first place.

Things aren’t simple, however. The forces that control elk populations are more varied than just wolves, or lions. Killing all the predators wouldn’t transform the Northern Rockies into a big game hunter’s paradise — though, frankly, it’s that already anyway.

The study examined predation on female elk and calves. Lions killed slightly more cows than wolves, and a significantly greater percentage of calves. That makes sense. A pack of wolves isn’t going to turn down an elk calf when the opportunity presents itself, but the pack is generally more interested in bigger prey that will fill more bellies.

But calves are just the right size for a lone lion. Every kill also presents the possibility of injury for the predator. That risk is certainly higher when preying on a full-grown cow elk rather than a smaller calf.

Apparently, the study didn’t look at predation on bull elk, but you don’t need a study to understand that wolf packs are a bigger threat to the boys with antlers. Taking on a bull elk with a full rack is culinarily ambitious, even for a big, experienced lion.

A pack of wolves is another matter. Biologists are documenting a trend that bulls are carrying their antlers longer into winter now that wolves have returned. Winter — when the snow is deep and bulls are worn down from the rut, the sparse availability of food and the struggle against frigid temperatures — is when the advantage tips most decidedly in favor of the wolf.

Bulls that hang onto their antlers longer are less vulnerable, but the tradeoff is that their racks will be smaller the following breeding season, making them less desirable to female elk.

Idaho biologists caution neither side in the wolf-elk debate should attempt to make too much of these results. Wolves aren’t killing all of Idaho’s elk, but that doesn’t mean the state’s wolf population should be allowed to grow unchecked. Hunting wolves still has a role.

For instance, the study also showed that pack size is important. As it increases, wolves are more likely to prey on elk, or other big critters such as cattle. That lesson was demonstrated in Kalispell more than a decade ago when nearly 30 wolves from the Hog Heaven Pack were killed after the pack began preying primarily on cattle to feed all those hungry mouths.

Yellowstone National Park biologists have added another layer of complexity to predator-prey interactions. A study from the park suggests that wolves and lions have predictable hunting patterns, patterns that elk seem to have learned, and have adapted their behavior to avoid being eaten.

Lions in the park prefer to hunt in rugged, forested areas at night. Wolves like the flats, hunting park-like meadows in the morning and early evening.

So elk head for the trees during the day when lions are resting, then to the flats at night when wolves are snoozing.

Again, if it were that simple, predators would never encounter elk. But these daily migrations to where the predators aren’t doesn’t eliminate encounters; it just reduces them. Hungry wolves and lions don’t clock out once their anointed hunting hours end. It’s just that neither species is as efficient outside its preferred hunting time and place.

The result is a balance that has left healthy populations of all three species in the park.