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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More Range Jumps

by Carl Strang

One recurring theme of my singing insects survey work is the northward extension of species’ ranges. Late in this year’s field season, three more species turned up significantly north of where I had found them before. One of these discoveries was made by Nancy Collins, who found broad-winged tree crickets (Oecanthus latipennis) half a county north of the Illinois border in Kenosha County, Wisconsin, more than 30 miles beyond where I had found them before.

Broad-winged tree cricket

I had not found this species in the northernmost row of Illinois counties, but I hadn’t looked for them there in recent years. Inspired by Nancy’s discovery, I did some searching and found them in Lake County at Chain O’Lakes State Park. Next year I want to seek them in McHenry County, Illinois, and Walworth and Racine Counties, Wisconsin (unless, of course, Nancy finds them there first).

The handsome trig (Phyllopalpus pulchellus) surprised me last year by turning up in sites across the southern half of my home county of DuPage in Illinois.

Handsome trig

I set the modest goal this year of seeking them in Kane County, just west of DuPage. Recently I succeeded in that, finding a group of them a little west of where I had found them in DuPage, but that was not surprising. What bowled me over was finding a small population of them in the East Main Street Prairie park in Cary. This is 22 miles, more than half a county, farther north, McHenry County being just north of Kane. This continued the pattern of handsome trigs popping up in separate scattered locations, because I tried to find them in northern Kane County and western Lake County, areas not far from Cary, without success.

The third species is one I have written about several times before, because it is spreading quickly, and soon becomes abundant in areas behind the front of its expansion. This is the jumping bush cricket (Orocharis saltator).

Jumping bush cricket

Last year I encountered a small population of jumping bush crickets in Wauconda, Lake County, Illinois. This was a good 12 miles north of where I had found them before. I still suspect that these were inadvertently transported there by people, and I wondered if they could reproduce successfully. Indeed there were even more males singing in that spot this year. The surprise was finding them in towns all along the west bank of the Fox River, nearly to the northern border of Kane County. This is a few miles south of Wauconda’s latitude, but a search of the southeastern corner of McHenry County, between the two locations, failed to turn them up. To be continued in future years…

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