Singing Insect Season Begins

by Carl Strang

In northeast Illinois there is a single insect species that each year is the first to produce a sound display audible to human beings. That is the greenstriped grasshopper, Chortophaga viridifasciata, one of the few singing grasshoppers we have in our area.

Greenstriped grasshopper male

Male grasshoppers produce songs in two ways. Some species rub their folded wings with their legs, emitting a zuzzuzzuzz… sound. This is called stridulation. Others, including the greenstriped grasshopper, perform short display flights in which they produce a rattling or crackling sound with their wings (crepitation). In the case of the greenstriped, the sound is a soft buzz or rattle, easy to miss if you are not listening for it. The fact that it is a display is demonstrated by the fact that grasshoppers flying to escape possible predation do so silently.

Greenstriped grasshopper females are grass green, in contrast with the slightly smaller brown males.

The first observed song date in this species is important to me personally, because singing insects are my main research focus. That date this year was April 3, and I heard several different individuals displaying that day. As I begin my 7th year of field study, this is by far the earliest start. The next two earliest were April 20 in 2010, and April 28 in 2006. The mild winter and warm spring got food plants growing early, and the overwintering grasshopper nymphs were able to complete their development in short order. I won’t be surprised to find a number of records for earliest song dates set by other singing insect species in the coming season.

1 Comment

  1. Gideon Ney said,

    April 26, 2012 at 5:17 pm

    Yes, we will have to be ready in a case of an equally early katydid emergence I think.

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