Periodical cicadas, like the Brood XIII bugs slamming the U.S. Midwest, have an unusual survival strategy: They simply ignore their predators.
"They don't do anything to get away. They don't fly away, they don't try to escape," said John Cooley, an evolutionary biologist at the University of Connecticut in Storrs.
Cicadas emerge in abundance—several million to an acre—so the overall reproductive risk of an individual getting eaten is negligible.
Even the most voracious eaters are unlikely to put a dent in the noisy insect population.
Fortunately for anyone bothered by the horde, adult cicadas die not long after producing eggs. Their offspring quickly disappear underground, not to be seen or heard from again for 17 years.
(Read "Cicada Facts: Understanding the Invasion" [May 21, 2007].)
Today scientists are using this boom-and-bust cycle of periodical cicadas to study the insects' effects on other animals.
What they are finding is that the oft-maligned insects likely play a key role in the life cycles of a variety of other creatures, from moles underground to squirrels in the trees.
Insect Bounty
Just about anything that can eat cicadas gorges on them during their emergence.
Spiders, praying mantises, and ants eat them. Dogs and cats eat them. Birds and fish eat them.
"[Fishing] lure manufacturers have designed cicada-shaped lures to capitalize on this fact," Dan Century, who runs the CicadaMania Web site, commented in an email.
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