Watch Two Stag Beetles Battle It Out Over a Female

Quick Take

• Female stag beetles don't just wait for a mate. They set off a chain reaction that turns their location into a battlefield. How pheromones spark the frenzy →
• Winning the fight is only half the challenge. The victor still has to pull off something unexpected before mating can happen. Discover the post-battle ritual →
• Neither beetle lives to see what their battle was fought for, and yet the species survives. See how the species carries on →

The life of a stag beetle (Lucanus cervus) is short and dramatic. Their mating rituals, as seen in this YouTube video, are more akin to a Shakespearean Tragedy. Males stage a fight to the death, while females bear sole responsibility for keeping the species going. When the two finally meet, their courtship is far from a love story.

In the bug world, survival of the fittest is often the only rule. And when it comes to stag beetle mating rituals, the emerging victor gets the girl, even if he has to prove his mettle first.

On Your Mark, Get Set, Crash Landing

During the stag beetle emergence from mid-May to late July, these insects have one thing on their minds: Finding a mate. Females aren’t always easy to locate, but males find them with a little help from pheromones. Female stag beetles release scents to lure a mate and then sit back and watch the drama unfold. Because when that love potion hits the air, a female isn’t only signaling to one male — she’s signaling to them all.

Once a male stag beetle latches onto the pheromone, the powerful scent kickstarts a frenzy. He rushes toward the nearest female, often crashing into her. At this point, mating is easy if he’s the first one to arrive. If he’s not, he’ll be forced to do battle with whichever males arrive at the same time. This is when things get messy, and there can only be one winner in this fight.

May the Best Suitor Win

When two male stag beetles lock mandibles, the winner comes down to strength and endurance. As seen in the video, not many fighting techniques are off-limits. Beetles may try to flip one another, stab each other with their sharp pincers, and even stand on two legs to get the upper hand. This aggression is fueled by the desire to reproduce, an instinctive drive that keeps the species alive.

While these fights look vicious, the goal is usually to display bravado rather than to kill an opponent. Fights typically end when one stag beetle tosses another, or when the loser admits defeat. Because of their intense nature, some stag beetles are overpowered easily if they don’t have the speed or strength necessary for the fight. Fatal blows are not often dealt, and most beetles walk away without serious injury other than to their egos.

A Curious Courtship Ritual

When only one male stag beetle remains, he turns his attention to the female. Before mating, he approaches her by offering a dance. This courtship ritual involves wiggling his mandibles and antennae to get the female’s attention. When she finally accepts his offering, they waste no time. Mating happens quickly, and often in the same spot where the male claimed his victory.

Depending on the environment, some stag beetles have been observed hanging upside down to mate. When this happens, the male typically holds the female with his mandibles while mating. This is another reason the stronger beetles usually win out over those that can’t hold their own. When the mating ritual is over, the female goes off to lay eggs almost immediately. Sadly, neither of them will live to see the newly laid eggs hatch. But they have succeeded in continuing their species, and the cycle begins again.