Not an Indicator?

by Carl Strang

Prairie cicadas are small, early-season cicadas that I first met on July 4 of last year at Woodworth Prairie in Cook County. Soon after that I found them at West Chicago Prairie and Belmont Prairie in DuPage County. Researchers at Woodworth have documenting them as emerging during a relatively brief period, mid-June to mid-July. This year I have been making weekly checks at West Chicago Prairie, and they did not appear until last Sunday, July 6.

This one sang from a bush clover stalk.

This one sang from a bush clover stalk.

That opened the door to seeking them on other sites, and I have been to two of them so far. I failed to find prairie cicadas at Horlock Hill Prairie in Kane County and at Wolf Road Prairie in Cook County. That spoils my working hypothesis that they would prove to be indicators of prairie remnants.

Here’s another West Chicago Prairie cicada, singing from a dead stem.

Here’s another West Chicago Prairie cicada, singing from a dead stem.

I hope to squeeze in a few more site checks in the next couple of weeks, but already I have the sense that this species is very limited in the locations where it occurs. I’ll also hope to get a sense of how long they are out at a given site. The July 6 appearance seems late, but this has been an odd year phenologically. So far the 11 species of singing insects have ranged from the earliest starting date in my record to nearly the latest, and the median is right in the middle. That is a little surprising given the severity and length of the winter, but first flower dates (which I hope to analyze soon) have been equally all over the place.

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Horlock Hill

by Carl Strang

Horlock Hill Prairie is regarded as one of the highest quality bits of dry prairie in northern Illinois. It is located right at the start of the Great Western Trail in Les Arends Forest Preserve in Kane County, and I have zipped right past it on my bike many a time without realizing its significance.

The designated natural area itself is small, at 2-3 acres, but I was impressed by the floral diversity.

Adjacent meadows and prairie restoration projects enlarge the effective area in prairie or prairie-like vegetation. In one of these I spotted a small meadow katydid which appeared at first to be a short-winged, but lacked the orange abdomen tip. He allowed me to get some photos, and when I looked at them later I was pleased to see the distinctive cerci of a straight-lanced meadow katydid.

The cerci are the little pincer-like structures at the tip of the abdomen. They are long, straight, abruptly flattened in the tips, and the small, inward-pointing tooth is near the base of each.

I found a female of this species at Mayslake Forest Preserve last year, but this is the first male I have seen. The only congeners I heard around Horlock Hill through the SongFinder were abundant short-winged meadow katydids. It was a cool, cloudy day, however, and the song of the straight-lanced is a steady uninterrupted faint buzz that may have been too faint to hear under those conditions. Certainly the short-wings were slowed quite a bit.

Otherwise the singing insects there were all of common species, except that I heard a couple probable broad-winged tree crickets. All of this points to a return to that site under warmer conditions.

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