Thermometer

23 August 2010

The sounds of nature are dominated by different animals as the growing season progresses in western Pennsylvania:

  • March and early April: Frogs
  • April, May, early June: Birds
  • mid-June, July, August: Insects

Crickets start and end the “bug noise” season with a chorus in mid June that continues right up to the first frost.  Until it freezes crickets don’t seem to care what temperature it is.  They just chirp faster in the heat, slower in the cold.

Did you know you can use a cricket’s chirp like an audio thermometer?  Count the number of chirps of a lone cricket for 15 seconds, then add 37.  Ta dah!  That’s the approximate temperature in Fahrenheit.

I’ve found this formula works well on a chilly September evening because the cricket chirps are distinct and slow but it fail my test on hot days.  I always wonder, did I miscount?

Click here to listen to fall field crickets (Gryllus pennsylvanicus) at the Songs of Insects.

 

(drawing of a female common black cricket, Gryllus assimlis, by R.E.Snodgrass of USDA from Wikimedia Commons; click on the image to see the original.)

p.s. The cricket in the illustration is female due to her long central “tail,” the ovipositor.