Seeking All the Answers

by Carl Strang

OK, the title is way too big for the subject of this post, but it’s not entirely wrong. As I complete my 6th season of singing insects study, there remain several species that range maps indicate should be in northeastern Illinois, but that I have yet to find. The past couple of seasons I have been going to places that match habitat descriptions for missing species, and I have added techniques to my repertoire. This has filled some of the gaps, for instance with the sphagnum ground crickets I found at Volo Bog. Now I am beginning to go to the source data on which those maps are built. Today’s example is the prairie meadow katydid.

This is the map for that species in the Singing Insects of North America website (SINA). It appears in the site’s page for the prairie meadow katydid, and as you can see it indicates a range that encompasses northeastern Illinois. SINA is the most comprehensive source of information about our singing insects. Created by Tom Walker, SINA is very clear and open about its methods. The maps are constructed by a computer program from a database you can download. The information for each dot on the map is in that database, and that is what I studied to further my search for the prairie meadow katydid.

A couple of things stood out as I focused on the Illinois and Indiana records for this species. First, all but one of the Illinois records are older than 1940. The same is true for all but four of the Indiana records. Things change, and I wonder if these data still are valid. Second, all the Illinois records appear to be from areas with sandy soil, as are at least most of the ones from northern Indiana. I am not so familiar with the southern Indiana sites.

Nearly all my field work has been in DuPage County, which lacks sandy soils. I conclude that I should return to places I began to visit this year that have such soils, and see if I can find this katydid there. Since it is one of the smaller meadow katydids, I will need to use the SongFinder to hear it, and may need to get permits to do some sweep sampling in order to see it.

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1 Comment

  1. October 13, 2011 at 5:44 am

    […] Last week I began a review of singing insects I expected to find in northeast Illinois but which I haven’t yet encountered. The next species in this series is the robust conehead. […]


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