Plant and Animal Care
Plant and Animal Care: Crickets
Background. Many people recognize crickets without even seeing them. They identify the familiar chirping sound made by the male cricket in his efforts to attract a mate. The sound is most often heard at night when crickets are most active, prowling about looking for food, moisture, and a consort. Crickets undergo simple, or incomplete, metamorphosis; they molt several times as they grow, each molt revealing larger, more fully developed crickets, until the last molt results in adults.
The female cricket has a structure protruding from the rear of her abdomen that students often think is a long stinger. It is an ovipositor, which the female thrusts into moist earth in order to lay her eggs well below the surface. When the eggs hatch, the nymphs dig to the surface, where they fend for themselves.
Crickets have other interesting features, starting with a pair of spikes that extend out from the end of the abdomen in both sexes. The cricket has two pairs of wings, the front two of which are equipped with rasp-like adaptations that, when scraped together, produce the chirp. The hindmost pair of legs are greatly enlarged, allowing the cricket to spring huge distances when motivated by alarm or other stimuli. On the front-most pair of legs are membranes that are sensitive to sound vibrations, so in effect the cricket has its ears on its legs. The antennae are long, lithe, and sensitive. It is fascinating to see the exquisite control the cricket has over these wispy structures as it probes and feels its environment before rushing in.
The cricket most used for classroom cultures is the house cricket. It lives in containers quite well and is content to eat seeds, fruit, grass, and dry dog food. However, crickets are good at escaping confinement. They will gnaw through paper or cardboard quite quickly, and if they are overcrowded, hungry, or thirsty, they will chew through nylon mesh covering a cricket container. For this reason it is necessary to cover the container with metal screen.
Cricket habitat. The FOSS cricket habitat has three chambers. One contains soil that is kept moist. This is where the females will lay eggs. A second chamber contains dry sand. Food should be placed in this area so that it will not mold. The central area is the exercise yard with structures for climbing and hiding.
Crickets need paper, sand, or soil to get around because their feet are not adapted for holding onto smooth surfaces. A large or complex cricket culture container will allow the crickets to display preference for variables such as moisture, temperature, and structure. Crickets prefer a hot, dry environment. If they are kept in a humid environment, they can develop a fungus, so lots of ventilation is needed. They can go into a moist environment to eat or lay eggs, but they must be able to retreat to dry ground. If you like, you can train a lamp on the central part of the habitat—the crickets will congregate there to bask. And you will probably get a song tossed in as part of the bargain.
What to do when they arrive. Crickets are shipped in a container with crumpled paper. They dislike overcrowding and should be transferred to a terrarium as soon as possible. To remove the crickets from the box, slit the tape. Enclose the box in a plastic bag and shake the crickets into the bag. Then transfer the bag of crickets into the cricket habitat you have made. This will be easier than shaking them directly from a box into the habitat. Crickets may be fed oatmeal, bird seed, small pieces of fruit or lettuce, or dried dog food. Prepare the water fountain provided in the kit. Crickets can also be purchased at pet stores or at stores that sell reptiles and amphibians.
What to do with the crickets when the investigation is completed. You can keep the crickets in a terrarium with a screened lid. Follow the care you’ve been providing and they should be fine. Crickets have a short lifespan so a long-term colony may not be possible. Offer the crickets to another classroom that will be conducting the investigation. They are also a good food source for reptiles and amphibians. Crickets should never be released into the wild as they may disrupt the environment and interfere with local organisms.