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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