Misconceptions about wolves are common. Many misunderstandings concern their hunting ability, with their killing ability often being exaggerated. Wolves hunt ungulates, hoofed animals, and routinely kill animals considerably larger than themselves, a feat few other predators can copy. This ability comes from their hunting in packs, rather than any outstanding physical characteristics.
Wolves have traditionally been difficult to study since wolf packs spend most of their time in heavily forested areas. Researchers on Isle Royale Island used aircraft to follow wolves and were surprised to find their primary prey, moose, routinely survived attacks by wolf packs containing up to 12 wolves. Other research found the same results when wolves preyed on caribou and white-tail deer.
Their re-introduction to Yellowstone National Park made studying them much easier. Wolves stay in open areas where they are visible to researchers. Their hunting techniques have been much easier to study. Wolves’ primary prey are elk, and wolves tend to kill mostly young, old and debilitated animals, with most healthy elk escaping their attacks. Most members of the elk population are animals wolves cannot catch.
Wolves are not especially adapted for killing large prey. They do not have a specialized skeleton for this killing. Their incisors and canine teeth are their only tools for grabbing and subduing prey. Their elongated snout means less biting pressure, compared to large cats with their flatter snouts. Wolf jaws cannot be locked or stabilized during bites like other predators. They also cannot use their limbs to grapple with prey like cougars and grizzly bears.
Wolves are the only North American predators that hunt in packs, and their physical limitations probably account for this fact. A single wolf has only about a 2 percent chance of taking down an adult elk and none at all of taking down a bison.
Even then, not all members of wolf packs are prime killers. The top-performing members are typically 2-3 years old, with older wolves not as helpful. Larger wolves, including the typically larger males, are better at pulling down prey. However, the smaller, faster females may be more help in pursuing running elk.
Researchers have noted that packs made up of four wolves seem to be optimal for killing prey. These packs have been more successful that smaller packs. Also, larger packs of up to 12 wolves are no more successful than packs of four. Four wolves seem to be able to grab and pull down large prey. Other wolves seem to hold back, perhaps to avoid injuries. The excess pack members above the primary four may pursue prey simply to make sure they are present for the meal.
Some packs in the park’s interior specialize in hunting the larger and more dangerous bison. These packs of up to 12 wolves are more successful in pulling down adult bison.
The information for this article comes from the Yellowstone Science publication titled “Celebrating 20 Year of Wolves,” an article titled “Understanding the Limits to Wolf Hunting Ability.”
Wolves tend to kill mostly young, old and debilitated animals, with most healthy elk escaping their attacks.