"I guess the 17-year Brood XIII cicadas aren't going to make it to Madison," concedes John Feith, a filmmaker and birdwatcher who headed south to Janesville on Sunday to view the garrulous insects in a rare above-ground appearance. "They rise from underground every 17 years and in a period of a couple of weeks shed their outer shells, make weird sounds, mate, lay eggs and then die," says Feith. "The next generation is born, goes back underground and eats tree roots for 17 years before coming back out."
The cicadas seen in Janesville are part of Brood XIII (also known as Brood 13 or the Northern Illinois Brood), one of 15 such groups around the Midwest, and last seen in 1990. Feith shot video of these particular bugs on the North River Road, along the Rock River, and notes that a much louder group could be heard at Cook Arboretum, which is known as among the best birdwatching locations in Rock County.
"I was told they mostly all emerged from the ground about a week or two ago, shed their shells and are now singing and mating," Feith says, who also observes that their nest holes are visible all over the ground.
The brief nature video, set to a little sci-fi background music, follows below.
"I've seen house sparrows eat them," notes Feith. "You hear the cicada buzzing along as the sparrow flies away with it. If you squeeze a cicada just a bit, it makes the same sound."
The filmmaker has a few jesting thoughts about the broods: "Some cicadas have a 13-year cycle. 17 and 13 are both prime numbers. Coincidence or proof of the existence of aliens?"