how do we know when it is the year of the cicada in Illinois?

Question

I read the the natural cycle of cicadas is 17 years, meaning that the last "year of the cicadas in the midwest, usa" would have fallen in 2004. but weather affects the cycle, so how do we know that what we hear are cicadas or related insects in the trees, making their mating sounds?

Answer 1

Here's a link (the first below) to a University of Michigan site that has a pretty comprehensive listing and maps of the various broods and emergence years of both 13- and 17-year cicadas. It turns out that in different areas of the country, the emergence differs.

Brood XIII of 17-year cicadas are set to emerge in the Chicago area and Northern Illinois in 2007.

(Brood X of 17-year cicadas emerged in 2004, mostly in Indiana, Kentucky, Tennessee and east.)

There is a dividing line in central Illinois, and another roughly along the Illinois-Indiana line, that separate different emergence years among the broods. Happy hunting!

Answer 2

Well, you are talking about Periodical Cicadas when they emerge thousands emerge at once so I am sure you will know!! However to differentiate you can listen and compare the songs of Annual cicadas to Periodical cicadas here.... http://insects.ummz.lsa.umich.edu/fauna/Michigan_Cicadas/Michigan/Index.html

Excerpt.... All but a few cicada species have multiple-year life cycles, most commonly 2-8 years (de Boer and Duffels 1996). In most cicada species, adults can be found every year because the population is not developmentally synchronized; these are often called "annual" cicada species. In contrast, populations of the periodical cicada species are synchronized, so that almost all of them mature into adults in the same year. The fact that periodical cicadas remain locked together in time is made even more amazing by their extremely long life-cycles of 13 or 17 years.

Periodical cicadas are found in eastern North America and belong to the genus Magicicada. There are seven species -- four with 13-year life cycles (including one new species described in 2000), and three with 17-year cycles. The three 17-year species are generally northern in distribution, while the 13-year species are generally southern and midwestern. Magicicada are so well-synchronized developmentally that they are nearly absent as adults in the 12 or 16 years between emergences. When they do emerge after their long juvenile periods, they do so in huge numbers, forming much denser aggregations than those usually achieved by cicadas. Many people know periodical cicadas by the name "17-year locusts" or "13-year locusts", but they are not true locusts, which are a type of grasshopper.

Magicicada adults have black bodies and striking red eyes and orange wing veins, with a black "W" near the tips of the forewings. Most emerge in May and June. Some of the annual cicada species are sometimes mistaken for the periodical cicadas, especially those in the genera Diceroprocta and Okanagana; these other species emerge somewhat later in the year but may overlap with Magicicada. The Okanagana species are the most potentially confusing because of their similar black-and-orange coloration. The best way to identify cicada species is by the sounds that they make, because cicada songs are nearly always species-specific. Recordings of periodical cicadas can be found below. To learn about some of the common annual cicada species of eastern North America (including the genera Tibicen, Diceroprocta, and Okanagana), and to hear their songs, see our Michigan Cicadas Page. Also check out the list of related links at the end of this page.

More Cicada info... Including brood maps and emergence information for your state... http://insects.ummz.lsa.umich.edu/fauna/Michigan_Cicadas/Periodical/Index.html

Answer 3

view this link hope it will help u
http://news.nationalgeographic.com/news/2004/03/0329_040329_cicadas.html