MTPR

Bug Bytes: Tiger Beetles

Feb 5, 2019

Imagine a grizzly bear that can run over 135 miles per hour.

Obviously, a grizzly can’t run that fast, but factoring in their smaller size, that’s what tiger beetles are to their potential prey.

Tiger beetles are the racecars of the insect world. They received their name from the combination of striped patterns on their bodies and their speed and ferocity as predators.

There are over 100 different species of these speedy beetles in North America. They’ve been clocked running at 1.38 feet per second (about 29 body lengths per second).

There’s even a tiger beetle in Australia that can run 170 body lengths per second. If a grizzly could do that, it would run faster than the speed of sound.

But there’s a downside to that blinding speed.

When running after a potential meal, tiger beetles display an unusual form of pursuit in which they sprint quickly toward their prey, stop and visually reorient, and then continue the chase.

Why? They actually run so fast that their brains are not able to accurately process what they are seeing, so they have to stop, look around and resume the chase. They literally run themselves blind.

But even taking the time for a few pit stops, tiger beetles are so fast they still have plenty of time to overtake the target of their high-speed pursuit.

Since they hunt by sight and chase down their prey with speed, they tend to live in sandy, gravelly open areas without a lot of plant growth that would get in the way.

So if you’re in an area with grizzly bears, be glad they’re not proportionally as fast as tiger beetles. But make no mistake, they’re still much faster than you.

BugBytes is made possible by the Missoula Butterfly House and Insectarium, and Montana Public Radio. This show is also supported by funding from the Greater Montana Foundation: Encouraging communication on issues, trends and values of importance to Montanans.