“Am I really hearing crickets already? Isn’t it too early for them?” “Did you just hear something down there in the grasses? It sounded like some kind of insect!” Yes, no, yes, and yes.
Crickets and katydids sing by rubbing a wing with a tiny scraper against another wing that has a tiny file. Many grasshoppers do not “sing,” but those that do will either rub a leg against a wing or snap their wings together in a sound-producing process called “crepitation.” Obviously, these sounds all require adult-sized wings.
But most of these insects are only eggs throughout the winter and into the spring. It will take several molts until the adult insects have developed the instruments they need to produce those sounds, which is why we do not hear them until summer.
Unless, of course, they overwinter as nymphs and got a head start on everyone else! The Spring Field Cricket (Gryllus veletis) and the Northern Green-striped Grasshopper (Chortophaga viridifasciata) do exactly that.
Their numbers quickly drop off in the first part of July as their adult season comes to a close. After a brief pause, the songs resume – but this time, the singers are the Fall Field Crickets (Gryllus pennsylvanicus). Once thought to be the same species, the Spring and Fall Field Crickets look alike and sound alike. The season is generally a reliable way to tell them apart, but it can be a little tricky during a cool, rainy year like 2011 or a hot, dry year like 2012 when insects mature late or much earlier than expected.
I have occasionally found Spring Field Cricket nymphs in the late fall, including several under a log at the upper edge of the beach at Mentor Lagoons on Lake Erie in Lake County, Ohio.
They seem especially fond of sandy soil and can be common along the ancient lake bed just south of the current shoreline of Lake Erie. Cleveland’s University Circle was built on that ancient lake bed, and Spring Field Crickets can be heard in this very urban area every May. I also hear them in other areas such as meadows, farm fields, gas well clearings, along railroad tracks, and in dry, open woods. I find Fall Field Crickets to be more common and widespread than Spring Field Crickets.
That subtle little fluttering sound down in the meadow vegetation is the Northern Green-striped Grasshopper.
It’s a short, soft song, and finding the individual responsible is no small task. They sometimes sing with a certain regularity, but more often you may find you attention wandering as you wait to hear the next statement of the “song.” There most likely will be more than one individual making these sounds, and it’s possible that one grasshopper could be making short, low flights to another nearby location.
The nymphs can be found in the late fall and on warm days during the winter, and they can be green or various shades of brown or tan. Because they are so small, it is easy to think they must be some kind of adult pygmy grasshopper – especially since they are already such powerful jumpers. You will probably have to enjoy watching them from a distance, as they are extremely difficult to catch.
Adults will generally be concealed in the meadow vegetation. Searching for them is well worth the effort, though, because they are very attractive insects. Their typical green and brown coloration blend perfectly with grasses and dried vegetation from last year.
It is especially rewarding – and not uncommon where I live – to find ones with pink as well as green color.
Although I am still very much engaged in bird song study, these early insect songs remind me that my favorite time of year will be here soon!
For more blog entries on the Northern Green-striped Grasshopper, I invite you to read entomologist Eric Eaton’s post here: http://bugeric.blogspot.com/2013/03/orthoptera-thursday-northern-green.html and naturalist Carl Strang’s post here: http://natureinquiries.wordpress.com/2013/05/09/singing-insect-season-opens-2/
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