Seeking Seasides

by Carl Strang

Coming into 2017, I had found seaside grasshoppers (Trimerotropis maritima) in most of the counties bordering Lake Michigan in the Chicago region. This band-winged grasshopper is mainly a beach-dwelling species, though it also occurs at Burnham Prairie, an inland site in Cook County

Seaside grasshopper, Indiana Dunes. This individual belongs to a population living on fine grained quartz sand.

The hind wings are bright yellow, and males can rattle their wings loudly in flight

Seaside grasshopper, Illinois Beach State Park. This one lives on a substrate of mixed fine stones ground by glaciers and waves. Selective pressures clearly have been at work on these hoppers.

Prior to this year I had found the species in Berrien, Porter, Lake (Indiana), Cook, and Lake (Illinois) Counties. In 2017 I added LaPorte County, and went up to Cliffside Park in Racine County, where GoogleEarth showed a narrow line of dunes and beach. I found, though, that storms and a risen lake level had removed these

The edge of Lake Michigan at Cliffside Park, looking north. Waves now wash right up to the cliff base.

Looking south from the same position.

I thought that might mean the end of the search, but a new GoogleEarth survey showed parks in the cities of Racine and Kenosha that looked promising. Both proved to have seaside grasshoppers, so now with the addition of Racine and Kenosha Counties I regard the Chicago region map complete for the species. I remain open, however, to stumbling across seaside grasshoppers at additional inland sites.

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