I love this time of year. Midsummer is a great time for a wide variety of reason. The pressures of spring-time mating is over for the birds and mammals. It is a time of abundance and relaxation for nature. But for me, this time of year is particularly interesting because of the insects at night. No I am not talking about mosquitoes, I am talking about crickets and katydids.
Summer nights are thick with mid-night music. The male common field cricket is the responsible for most of the songs. Field crickets are members in the family of “true” crickets. They have large broad bodies up to 1-inch long and have large strong hind legs for jumping great distances. They have very long antennae that are nearly as long as the body. Females have a long needle-like appendage extending from back of their abdomen called an ovipositor, for laying eggs into the soil. Males have large obvious wings that carry them around at night.
Crickets are closely related to grasshoppers. There are over 23,000 species of crickets and grasshoppers in the world. There are nearly 1,000 different kinds of grasshoppers and crickets in North America.
Male crickets don’t sing with their voice, they sing with their wings. They have two pair of wings (total of four). The front or upper wings are the cricket’s instrument. They play their wings like a violin. The larger hind wings are for flying.
A row of tiny ridges, much like a woodworker’s file, located on the underside of the front wings are rubbed against a thickened region, called a scrapper, along the edge of the opposing front wing. While both wings can either file or scrape, most male field crickets are what researchers call “right winged”–the right wing passes over the left, with the right file and left scraper producing the song. Left-hand male crickets are just the opposite.
Unlike most birds and mammals, the field cricket waits until late summer to mate. Male crickets sing to attract a mate. While the female is the silent partner, she has excellent hearing. After all, it is her hearing that will guide her to a prospective mate. She doesn’t have ears like you and I. Her ears are located on the knees of both front legs and are sensitive only to different sounds made by the males.
Not all male crickets serenade their mates. Some will silently hide within the territory of another singing male cricket waiting for a female that is attracted by the signing male. The silent male than intercepts the incoming female. The silent male is called a satellite male because he orbits around the singing male waiting to intercept a prospective mate.
After mating the female uses her long needle-like ovipositor to individually inject several hundred eggs into the soil. The eggs will over-winter and hatch next spring. Only adult crickets in the warmth of your basement will make it over winter. The young hatch into miniature looking crickets and will slowly grow into adults. Crickets grow by shedding their hard shell-like skin in a process called molting. They go through eight to twelve molts to become adults. That’s why you never hear crickets in spring. They are just too small and haven’t matured into singing adults yet.
The snowy tree cricket, a relative of the field cricket, is sometimes called the temperature cricket because it’s temperature sensitive. This small green cricket chirps more times per minute when it is warm than when it is cold. Snowy tree crickets sound like jingling sleigh bells. If you count the number of chirps in 15 seconds, and add 40, you will have a good approximation of the air temperature in degrees Fahrenheit.
Tonight take a minute to step outside after dark and tune into the magical nighttime music. Until next time
Stan Tekiela is a author / naturalist and wildlife photographer who travels the US to study and photograph wildlife. He can be followed on Facebook.com and Twitter.com.