Super long antennae help camel crickets navigate dark places like tools sheds.
One day last week, my morning shower was interrupted by a camel cricket ricocheting off the sides of the bathtub. This dromedary of the insect world is so named for its humpbacked appearance. Like their cousins the field crickets, camel crickets (a.k.a. cave crickets) have extraordinarily long hind legs and prodigious antennae. The antennae bear sense organs that enable camel crickets to detect food and avoid predators in dark, damp habitats such as deep woodlands and caves, in which they live. In a realm of perpetual darkness where eyesight is of little value, some cavernicolous species of camel crickets are blind. My outdoor colony of camel crickets occupies a moist leafy redoubt behind a rubbish bin along the shaded, northern aspect of my foundation. Camel crickets are also found in damp woodpiles, dense vegetation, and refuges beneath rocks, where they consume decaying organic matter such as leaves, roots, and fruits. They also devour rotting remains of other insects, including their kin. Indoors they are occasional pests because they nibble stored fabrics.
Sensory structures on the antennae and mouthparts help camel crickets decide what to eat and what to avoid.
Their annual home invasion begins in the late summer and early autumn when they appear in basements, garages, and crawl spaces with high humidity and low light levels. Like boxelder bugs, stink bugs, lady beetles, and field crickets, camel crickets enter homes through portals such as cracks in the foundation, voids around basement windows, spaces beneath doors, and holes where plumbing and electrical utilities exit and enter. Little crickets enter early in the season and often go unnoticed, but as they scavenge food and grow in size, they become more apparent. Though wingless, they have remarkable powers of locomotion. Long, powerful legs provide an uncanny ability to jump. As I chased my visitor around the shower stall, it easily cleared the edge of the tub - a leap ten times its own height. While this feat might seem trivial, in human terms this would be equivalent to LeBron James slam-dunking at a rim 60 feet above the court. That’s some kind of leap.
Camel crickets may shed a leg when threatened by a predator.
After an energetic chase, I finally corralled the cricket in a corner and gently nabbed it. To my surprise, there on the floor where the cricket had been, a disembodied leg flexed in what appeared to be a macabre search for the rest of the cricket’s body. The strange behavior of discarding an appendage when attacked by a predator is not uncommon. Many insects, including crickets and walking sticks, are able to shed a limb on command. A special muscle allows a leg or antenna to snap off at the insect’s bidding under the right circumstances. This phenomenon, known as autotomy, allows the insect to lose a leg and save its life by distracting a hungry predator. When the predator stops to examine or eat the severed limb, the bug makes it getaway. Sometimes the insect regenerates the missing part. In addition to insects, several species of reptiles, birds, and mammals use this clever ploy. With the Thanksgiving banquet still a vivid memory, the cricket’s leg reminded me of a turkey drumstick. I could not help but ponder the disappointment some poor predator felt when its camel cricket feast had one drumstick instead of two.
Here are some helpful tricks to keep these curious crickets out of your home. Remove woodpiles and vegetation near the foundation of your home. These refuges are ideal sites for camel crickets to multiply and later enter your home. Caulk and seal all openings to the outdoors around the foundation. Replace and repair door sweeps and reduce levels of humidity in the basement. If you find crickets inside, you can capture them with a vacuum or in a jar. Sticky traps such as those used for snaring roaches can be placed on the basement floor. I have found the corner junction of two walls to be a productive spot for catching crickets as many species like to travel with a shoulder near a wall – a behavior known as thigmotaxis. So, the next time you try to capture one of these troglodytes of the cricket world, see if it leaves a leg behind for you.
After dropping a leg, this little camel cricket ambled across the bathroom floor.
References
Two great references used in preparing this Bug of the Week were the article entitled “Autotomy in a walking stick (Insecta: Phasmida)” by Tara Lynn MaGinnis, and “The Insects: An outline of Entomology” by P.J. Gullan and P.J. Cranston.
To learn more about camel crickets, visit the following web sites:
http://www.ces.ncsu.edu/depts/ent/notes/Urban/camelcrickets.htm
http://www.ipm.iastate.edu/ipm/iiin/ccamelcr.html