Spring Field Cricket Final

by Carl Strang

July brings the transition between the two sibling species, spring field cricket and fall field cricket, which look alike, sound alike, and differ mainly in their season. As the year has been a little on the late side, I felt comfortable in extending my study of spring field cricket geography through the 4th of July. Here is the updated map of DuPage County showing known locations for the two species.

Green circles mark where both spring field crickets (SFC) and fall field crickets (FFC) occur. Yellow circles indicate FFC-only, clear blue circles indicate SFC-only. Red areas indicate where there are no SFC, but FFC status is undetermined. Blue circles with question marks and blue stars indicate places where SFC have been found, but FFC status is undetermined.

In most of the western two-thirds of the county, both species occur together. There is a substantial area in the eastern part of DuPage where SFC are absent. The blue circles with question marks are along the Burlington Northern railway. I am beginning to get the idea that, much as I found with periodical cicadas, the history of land use in the county may have had a profound impact on the geography of spring field crickets.

Spring field crickets appear to have a narrower habitat range than fall field crickets. They seldom are to be found in wooded areas, or in open areas that are mowed. The early conversion of agricultural lands and woodlands to residential and commercial areas in eastern DuPage favored periodical cicadas, which expanded into the new urban forests people planted in the towns. If my new hypothesis is correct, this same change was disastrous for spring field crickets, which could hang on in the unmowed fringes of agricultural western DuPage of the 19th and early 20th centuries, but were driven out of suburbanized eastern DuPage.

Once July has passed, SFC will be done and FFC will be well under way. I will check the areas marked in red and with blue question marks to continue refining my data.


1 Comment

  1. August 22, 2011 at 6:04 am

    […] that was quiet in the spring, scattered fall field crickets were singing. Later in the spring I checked some additional sites. On Saturday I went back to these, and again in every location found fall field crickets. Here is […]

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