St. Louis ? The shiny black beetles that have descended on Busch Stadium in recent weeks may be a nuisance, but they won’t hurt anyone.

That’s according to Saint Louis Zoo bug expert Bob Merz, who said the sturdy, tank-like insects with the hard shell body are just passing through, perhaps in pursuit of a mate.

Merz, the zoo’s manager of invertebrates, said the “ground beetles,” about a half-inch to three-quarters of an inch long, take flight to find their special someone.

He said they would move on to the next destination in a week or so. Those that escape extermination, that is.

Mike Bertani, director of operations at Busch Stadium, said Tuesday the beetles were being sprayed this week while the Cardinals are away.

“We have a problem. We’re spraying for them,” Bertani said, declining to comment further.

Fans say they’ve seen the beetles hovering around the lights and bouncing around in the stands. Some are known to make a clicking sound.

In the insect’s oh-so-brief life, basically a year, it transforms from an egg to larva to a pupa, the early stage of its becoming a beetle, usually in June and July.

It pops out of the ground in mid-July to August for its fourth and final stage – as an adult beetle – when it looks for a mate to produce the next generation.

Warmer temperatures may have sped up the process this year, Merz said.

The stadium’s bright lights and abundant food source – other insects – probably attracted the beetles, he said. When they eat, they emit a scent designed to attract a mate – to start the life cycle all over again.

“I don’t see this as an ongoing problem,” Merz said. “It probably will right itself in the next few weeks.”