Thursday, August 19, 2004

The Sound of Crickets

It has been an unusually warm summer here in the Northwest. With the warmer evenings I have noticed an old familiar "song" that reminded me of my years in Arizona. Crickets. I had been living on the coast, and never heard them there, so I got curious as to the why I now heard them in the city. I made a mental note to consult "the professor" (my nickname for google when I have a question) to find out the whys and hows of these noisy little bugs.

Only the males make noise. That's right guys, you won't hear ONE SOUND coming from the females. The males chirp to attract the females. This chirping is created by something called stridulation, which is the term used to describe when one body part of an insect is rubbed against another part of their body. They use their front wings to make the sound. One cricket was listened to by a zoologist who documented his chirping of no less than 42,000 times over a period of four hours! (this documentation might of been different if the zoologist had provided a female or two to listen to the poor little fella). Unfortunately in the great outdoors they make such a racket that the noise also lets predators know their location. It is amazing what sort of danger a male will expose himself to, to do what he's gotta do. One cricket source even said that once the male has succeeded with attracting a female to mate, he dies. And we thought our life is tough.

I discovered a few more interesting facts about these eco-friendly good for your soul little insects. In China ladies from the Imperial Palace kept crickets in golden cages to provide soothing "music" as they went to sleep. They are nocturnal omnivorous who some say you can use to determine temerature by the number of chirps. Someone even came up with a formula to do this!

The simplest method is to count the number of chirps in 15 seconds and add 40. The sum usually approximates the temperature within a few degrees Fahrenheit.

The original formula for determining temperature from cricket chirps appears to have been published in 1897 by A.E. Dolbear, a physics professor at Tufts College. Since Dolbear’s time, formulas have been devised for various species. Here are Three formulas which may or may not actually work! In all cases, T is the temperature and N is the number of chirps per minute.

Field Cricket: T = 50 + (N - 40 / 4)

Snowy Tree Cricket: T = 50 + (N - 92 / 4.7)

Katydid: T = 60 + (N - 19 / 3)

I am getting much to carried away with all of this! When I all I wanted to do with this blog is to clear my conscience of a cricket experience I had when I returned home to visit Arizona. I had been living in Alaska for quite a few years and had even forgotten the soothing night noise that these guys orchestrate. So I was actually excited when I heard a cricket in my room the first night home. All I can say is that if you put one horny cricket in a room with an exhausted traveler...the can of Raid will be brought out and the need to silence the mating call will override even the kindest spirit. In my defense, my intention was originally not to destroy the little guy. He was in my room though! He would sing, I would turn on the light (to gently remove him to the great outdoors mind you) and he would shut up. Light would go out, I would lay down, and he would start up again. Repeat scene. Light on, silence, look around, light off. By three in the morning after an attempt to slam a window on him, the can of Raid was grasped in my hand and I was looking to silence him once and for all. I never found him, I woke up with my hand still clasping the can of Raid.

I guess now I am glad I never did find him...


information obtained from:
"House Cricket" Stuart M. Bennett
"Crickets and Temperature" entomology.unl.edu/(k-12)



No comments: