A shortcut to what is called Dolbear's Law suggests that we isolate the sound of a cricket, and then for 15 seconds, count the chirps that come from the insect. In the 19th century, a scientist named Amos Dolbear correlated air temperature and the chirp rate of crickets. And then, it will be about an eight-month wait for the crickets of Southeast New England to call again. First frosts will kill some of the insects. Indeed, crickets grow quiet, as fall sets in. The insects slow down and their chirping weakens. In warm air, they chirp easiest, but as conditions chill, so do crickets. Given that crickets are cold-blooded creatures, they take on the temperature of their surroundings.

Last week, when nighttime temperatures dipped into the 40’s, I noticed that the crickets outside our home quieted and their chirping slowed.

Indeed, other crickets, such as the tree cricket, click so fast that all we hear is a vibration or trill discernible from a significant distance. The human ear cannot detect that each of those chirps is actually a rapid three- to five-pulse trill. Other crickets, such as the clear, noisy chirps of a field cricket (the common, large, black-bodied creature that people most-commonly recognize) come at rate of about one-per-second. Some crickets give a slow rub that produces a click. The resulting sound is called “stridulating.” Male crickets chirp by rubbing together the upper part of one wing and the lower part of another. Teeth-like ridges cover the bottom of a cricket wing, while the top of a cricket wing is similar in structure to a scraper. GET THE LATEST BREAKING NEWS HERE - SIGN UP FOR GOLOCAL FREE DAILY EBLAST Research suggests that female crickets find louder-and-more-strident-chirping males the most attractive. They chirp for the same reasons as male birds-to attract a mate and defend a territory. Some of the insects produced continuous humming or buzzing sounds, while others clicked. Crickets chirped at the ground level, within eye-level vegetation and even in the trees. Last weekend, Karen and I walked on the Ten Mile River Greenway behind the Kimberly Ann Rock Memorial Athletic Complex in East Providence. As birds quiet down over summer, crickets rev up their chirping, a sound that I associate with the coming of fall.

Cricket sounds