Every year, male elk face a tough decision: either grow bigger antlers to be able to attract mates or keep their old antlers longer to better protect themselves against predators such as wolves.
The conundrum is the focus of a new study by researchers from the University of Montana who studied the elk population in the Yellowstone National Park.
Purpose Of Elk Antlers
To understand the problem of male elks, it is important to know what antlers are used for.
The antlers growing on the heads of male elk have two purposes. The first is to attract female elk, with bigger antlers making them more preferable mates. In addition, male elk may lock their antlers in battle to win the favor of a female elk.
The antlers, however, have an important secondary function, and that is to protect themselves from predators. In Yellowstone National Park, these predators include wolves, which are among the most intelligent hunters in the animal kingdom.
Male Elks: Bigger Antlers Or Safety?
A study by University of Montana researchers, published in the Nature Ecology & Evolution journal, focused on a decision that male elk need to make each year.
Elk regrow their antlers every year, with the antlers becoming bigger and better, as more time is provided for their growth. Some elk drop their antlers to start growing new ones by early March, while others, mostly the younger elk, keep their antlers until the end of April. This gives the male elk several months before mating season in the fall.
It was unclear why the male elk shed their old antlers in different times, but wildlife biologists believe that they have found their answer while observing the elk and wolves in Yellowstone National Park. Analyzing data over a dozen years, the researchers determine that wolves target male elk that have lost their antlers. Wolves hunt male elk with no antlers even if they are healthy, which is contrary to previous knowledge that the predators focus their hunt on weak or sick prey.
The discovery revealed the tough decision that male elk face each year. If they shed their antlers early, they increase their chances of finding a partner in the next mating season but also with a higher risk of falling prey to wolves because they have no antlers to protect themselves. If they keep their old antlers on longer, they will be safer but may be less attractive when mating season rolls in.
The researchers claim that this decision likely influences the evolution of the species over time. North American deer, in particular, choose to retain their antlers longer, choosing their safety over being a preferential mating partner.