How Bugs Drive Baseball Batty

"O.K.," I said, "but what about the flying insects that visit Royals Stadium at night? Where are they?"

"Outside," she said.

It turns out there is a valley just south of the Truman Sports Complex, where the Little Blue River winds eastward through a dense growth of trees. We parked in a lowland meadow lush with wildflowers and tall grasses, and went into the trees. We couldn't even see the stadium light towers through the foliage, but I could picture in my mind the scene at night—the woods dark and silent, and above the treetops an intensely bright blue-white corona that lured clouds of moths to the stadium. Why, I asked, do moths love lights so much?

The fatal attraction of moths to night lights, Ramoska said, is not fully understood by scientists. There are, however, some attractive theories. "I suspect it's some primitive aggregation phenomenon, a way for a moth to meet a mate. They'll fly right into a flame. Tens of thousands probably die in the lights during every ball game."

We came to a series of small puddles and muddy depressions. "This is where your stadium mosquitoes breed," Ramoska said.

"And they fly to the stadium because the lights are on?" I asked.

"Not necessarily. Flying insects are attracted to different things," he said. "For gnats, it's heat. For moths, it's light. For mosquitoes, it's respiration."

"The female mosquito needs a blood meal to produce eggs," said Bertholf, "so it homes in on the CO[2] breath."

"And smell," Ramoska broke in. "Ballplayers, when they perspire, give off a chemical called adenosine triphosphate, or ATP. Mosquitoes zero in on it. That's why some people get bitten more than others. Hyper people—people with a fast metabolism—give off more ATP than most of us, and therefore they draw more mosquitoes."

So the ballplayers cause squadrons of mosquitoes to fly toward Royals Stadium every time there is a game? Not quite. Ramoska said most mosquitoes are poor fliers, and they escape their breeding grounds only when they are carried away on a brisk wind. "The average mosquito dies within a hundred yards of where it is born," he added.