Jumping North

by Carl Strang

Of the many species of singing insects that have expanded their ranges northward in the past half century, the jumping bush cricket (Orocharis saltator) has been the fastest mover in the Chicago region. I have done my best to keep up with them ever since 2007, when I first heard their bell-like chirps in DuPage County, Illinois. As their density built dramatically in southern DuPage, the front of their advance typically shifted half a mile north each year.

Jumping bush cricket

At the same time, they were on the move to the east in Cook County. I first found them in Kane County, to the west, in 2014. The line of their advancing front has angled southwest to northeast, suggesting an Indiana source of the invasion, though last year I heard them singing just north of Peoria, well southwest of the Chicago region.

Over the past couple of years, what seemed to be a simple spread has become complicated. First, the advance apparently stalled out in the northeast corner of Cook County, just south of the Lake County border. Farther west, however, the crickets’ expansion has, if anything, accelerated. Following the Fox River, they have moved 8 miles up its east bank in 3 years.

But that’s not all. This year I found them even farther north on the west bank. Then, on September 20, I heard jumping bush crickets singing at the edge of Wauconda, in western Lake County. Subsequent checking revealed that this is an isolated small group, probably a human-assisted introduction. I will be interested in seeing if they successfully reproduce there. In any case, there is no end in sight to the dramatic northward movement of this species, and I will continue to invest some time each year in documenting it.

Map of the Chicago region, showing locations for jumping bush crickets. Black dots indicate counties where the species has become established. Stars indicate farthest north locations: red for 2014, yellow for 2015, green for 2016, and the two blue stars indicate new north locations in 2017, along the west bank of the Fox River in Kane County, and at Wauconda in Lake County.

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Handsome Trig Hijinks

by Carl Strang

Last year I followed a tip from Joe Balynas and found handsome trigs (Phyllopalpus pulchellus) established along the Cal Sag Channel, an extension of the Calumet River, in southern Cook County. This apparently was the first finding of the species in northern Illinois.

The handsome trig’s scientific name translates to something like “beautiful little leaf-mouth,” a reference to the expanded tips of its palps.

The Cal Sag Channel points toward the southeast corner of my own DuPage County, and I resolved that this year I would follow the trails along that waterway, and discover how far the trigs had come. That plan was blown to pieces on August 18. I was running along a recreational trail in Wheaton, central DuPage, when I heard the ratcheting mechanical trill of a handsome trig. I stopped to search, and was amazed to find four of the little crickets on the underside of a burdock leaf. Over the following weeks, I heard handsome trigs in scattered other locations in the southern half of DuPage County. I went back to southern Cook, and rode my bicycle west along trails that follow the Des Plaines River, past the point where it forms a complex with the Cal Sag Channel and the Chicago Sanitary Canal. Handsome trigs were audible at intervals along the trail, all the way into DuPage County’s Waterfall Glen Forest Preserve. This was one route by which the species may have reached my county.

What the hey? I have been able to recognize the handsome trig’s song for years, now. I had not found them in my own home county until 2017, and now suddenly they are in scattered spots across southern DuPage. Something about this year has favored the species, as they seem to be more numerous across the Chicago region. In 2017 I also added records for Will County, Illinois, Starke County, Indiana, and Berrien County, Michigan. This last is a new find for southwestern Michigan, but not for the state, as a recent paper reported them in southeastern Michigan (O’Brien, Mark F., and Julie A. Craves. 2016. Phyllopalpus pulchellus Uhler, the handsome trig (Orthoptera: Gryllidae), a confirmed Michigan resident. Great Lakes Entomol. 49:202-203).

The handsome trig is another species of singing insect that is expanding its range northward. It seems reasonable to think that they quietly have been spreading in DuPage County for years, but conditions in 2017 elevated their little local populations to the point where they drew my attention. I will be interested in following their numbers and possible ongoing range extension in coming seasons.

Slightly Musical Coneheads Extend West

by Carl Strang

The slightly musical conehead (Neoconocephalus exiliscanorus) bears my favorite common name among all the singing insects of the Chicago region. That name was bestowed because W.T. Davis, who first described the species in 1887, thought its song was faint. He later changed his tune for good reason, as I find I can hear them easily through the open window of a car driven at a moderate speed. This was, in fact, how I came to add the slightly musical conehead to the species list for the Chicago region. Previously it was unknown in the northern third of Indiana, so I hadn’t expected to find it. Then, prowling the roads of the Indiana Dunes National Lakeshore with me in 2012, graduate students Gideon Ney and Nathan Harness, of the University of Missouri, recognized the katydid’s distinctive rapid buzz pulses.

Slightly musical conehead. They can be brown or green, and have longer cones at the tips of their heads than our other species in genus Neoconocephalus.

Subsequently I found slightly musical coneheads in several northern Indiana counties. They have not been a priority in my 22-county survey of the Chicago region’s singing insects, but I may make them one next year. In 2017 I added three counties: LaPorte and Lake in Indiana, and Kankakee in Illinois. Those last two additions extend the range significantly west, and provide the first observation of the species in the northern half of Illinois, according to the database in the Singing Insects of North America website.

Here is the updated map of my observations for this species:

Black dots represent the counties where I have found slightly musical coneheads through 2017.

And here is a recording of the song:

I often hear them singing in rural roadside ditches, and they are increasingly abundant as you go south. They sing only at night, in my experience.

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