Mantid Season In Michigan
September 19, 2013
Recently, I have been noticing a lot of praying mantises out and about in Southeast Michigan. I knew that there were praying mantises in the state, but I'd never seen so many as I have recently. And so large! These were noticeably big, often a mottled brown color, and active in the evenings. As I didn't know a lot about mantises, I got curious; and in satiating my curiosity I learned a lot about these fascinating little creatures.
Michigan has, as it turns out, two species of mantis flying around. Actually, not even mantises -- according to National Geographic, they're more properly called mantids, as "Mantis refers to the genus mantis, to which only some praying mantids belong."
And in fact, the larger of the two Michigan species does not belong to the genus mantis. Instead, it is Tenodera aridifolia, commonly called the Chinese mantis or Chinese mantid.
The Chinese mantid is one of the largest mantids in North America. Some specimens grow up to four inces long. Chinese mantids tend towards browner hues, with some green on the sides and legs. Like all mantids, they can fly; and let me tell you, having a four-inch mantid flying towards your head can really freak you out.
The other Michigan species is the "real" Praying Mantis -- Mantis religiosa, the European mantis, which has lent its moniker to the entire genus.
The European mantis is smaller than the Chinese mantis, measuring 2-3 inches on average. They also have the most distinctive "mantis" structure -- the prominent folded legs, the V-shaped head, the leafy green exterior.
As their names imply, neither Michigan mantid is native to the region. Though they have been on this continent for more than a hundred years (long enough that some sources peg the American versions as subspecies), they were imported, probably by farmers looking for some pest control. Mantids are carnivores, and they will prey on smaller, more annoying bugs; unfortunately, the reality is that most mantids don't have a large hunting range, and so their practical use as a garden pest deterrent is limited.
The reason I've been seeing so many lately is because this is their mating season. Mantids hatch in the spring, spend the summer maturing, and then get busy in autumn before they die. The eggs laid in the fall will weather the Michigan winter before releasing the next generation in the following spring.
Since I'm talking mantids, I should probably address the head-biting-off thing. Do female mantids bite the heads off of males after mating? Sort of. As it turns out, the female mantid is just always hungry, and sometimes fancies a meal even in the middle of being impregnated. Mantids have no problem being cannibalistic -- growing mantids will eat one another if there's scarce prey available -- and so if it strikes her fancy, her mate is the closest food source. And she doesn't just bite the head off; she will feast on her mate.
As I write this, Southeast Michigan is just coming out of a cold snap that had frost advisories for the area. Thus, it's possible that the Michigan mantid die-off has already begun. But I'm sure they'll be back next year.
Barnes, J. K. (2005, October 26). Chinese mantid. University of Arkansas Arthropod Museum. Retrieved from http://www.uark.edu/ua/arthmuse/chiman.html
Bodin, M. (2012, August 27). The truth about praying mantises. Northern Woodlands. Retrieved from http://northernwoodlands.org/outside_story/article/truth-about-praying-mantises
Myers, P., et al. (2013). The Animal Diversity Web. Retrieved from http://animaldiversity.org
Praying mantis (Mantis religiosa). (n.d.). National Geographic. Retrieved from http://animals.nationalgeographic.com/animals/bugs/praying-mantis/
Tree of Life Web Project. (2003). Retrieved from http://tolweb.org/
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