A Pause in the Action

by Carl A. Strang

In the early part of the season, from April to early July, my research focus is on those species of singing insects which matured from overwintering nymphs, plus some small early-season cicadas. This is a minority of species, as most of the crickets, katydids, and singing grasshoppers mature after the middle of July, having wintered as relatively secure eggs and needing time to grow up.

I was able to close the book on northern wood crickets last month, and the story here is a sad one. This forest-dwelling member of the field cricket group had been reported from two northern Indiana sites by W.S. Blatchley in 1903. As far as I know, no one has sought them since then in the northern part of the state. Last year I determined that they no longer occur where Blatchley found them. This year I checked the largest other eight forests in the Indiana portion of my study region. If they ever were there, they are gone now. I suspect that forest fragmentation for agriculture and other purposes is responsible for the loss. Blatchley’s detailed descriptions leave no doubt that he knew how to recognize the species.

This northern wood cricket is from the northernmost site where I know they still occur, Eagle Creek Park in Indianapolis.

I was able to close the book on another southern species, the spring trig, in June.

This tiny, early-season cricket is common in southern Indiana.

I have found a few scattered groups of spring trigs in southernmost Fulton and Jasper Counties in Indiana. A thorough search failed to turn them up in neighboring Pulaski and Newton Counties. I may check again in a few years, on the possibility that the species is expanding northward.

One positive result was finding sulfur-winged grasshoppers in the East Main Street Prairie of Cary, Illinois. This adds McHenry to the counties where I have found the species. They probably occur in every county in my region but are common only on sandy or gravelly soils such as Cary’s kame-like hills. I have learned of another candidate site which may add Fulton County, Indiana, next year.

Sulfur-winged grasshoppers are characterized by bright yellow hind wings, which they rattle in flight to produce their song.

Prairie cicadas started a little late this year. I was pleased to find that management efforts to remove brush from the West Chicago Prairie Forest Preserve near my home appears to have paid off in both rebound of diverse prairie vegetation and an increase in the cicada numbers.

Prairie cicadas, are tiny, around an inch long.

Failure to perform such restoration work has a cost. Once known to occur in Kankakee County, prairie cicadas apparently are gone from there, the prairies having been degraded by brush, teasel and other invasive plants.

A final story is that of the periodical cicadas. In each cycle since 1973, the main appearance of 17-year cicadas in Chicago’s western suburbs has been preceded by a significant, 4-year-early emergence. This happened in 1969, 1986, and 2003. I suspect that in a small part of this area, all the cicadas now have switched to the early time. If you have done the math, you realize that it may happen again next year. One predictor to watch for are what I call oops cicadas, a few individuals who jump the gun by a year, or miss the main emergence and come out a year late. As expected, this has been happening this spring. I have heard 3 individuals myself in two cities and seen photos of the insects from 3 more. Counting and mapping them will be a highlight of next year’s early field season.

I predict that some areas will have good numbers of 17-year cicadas next year.

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Closing the Book on Sulfur-wings

by Carl Strang

The sulfur-winged grasshopper is an early season species that I wanted to close out this year, in my regional survey of singing insects. Though it probably occurs in all 22 of the counties in my survey region, it is common only on soils heavy in gravel or sand. I targeted 3 counties with such soils where I had not yet found this crepitating (wing-rattling) grasshopper: Walworth in Wisconsin, LaPorte in Indiana, and Berrien in Michigan.

Success came first at the Lulu Lake natural area in Walworth County. I did not find it in the Nature Conservancy portion of the property, but gravel-hill openings in the forest on the state nature preserve side proved to have a good population.

One of the series of photos documenting sulfur-winged grasshoppers at Lulu Lake.

Subsequently I found them in the Lake Michigan coastal zone in LaPorte and Berrien Counties. In the process I learned a final lesson from the grasshoppers: they don’t like loose dune sand, and need to be sought a little farther inland, where plants and the accumulation of organic matter have made the soil more stable. That closes the book on sulfur-winged grasshoppers as far as my survey is concerned, and I will put my time into other species at this point of the season in future years.

The updated Chicago region sulfur-winged grasshopper map, marking counties where I have found it.

 

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