Super long antennae help camel crickets navigate dark places and powerful legs help them escape nosy entomologists.
Recent episodes of Bug of the Week featured invaders from Asia including Emerald Ash Borer, Brown Marmorated Stink Bug, and Kudzu Bug, but in the last week or so, Asian camel crickets captured the attention of the national media. A fascinating new study revealed that Asian camel crickets had bested our native camel crickets as rulers of residential man-caves and basement bedrooms. Researchers in North Carolina State University conducted a national survey and discovered that in places like Maryland, Virginia, and the District of Columbia, more than 90% of the camel crickets found in homes were Asian camel crickets.
Camel crickets in the genus Diestrammena were first detected in the United States in a greenhouse in Minnesota in 1898 and dubbed the greenhouse camel cricket. Who would have guessed that in little more than a century they would become a dominant home invader? These dromedaries of the insect world are so named for their 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 the 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.
Sensory structures on the antennae and mouthparts help camel crickets decide what to eat and what to avoid.
Camel crickets consume decaying organic matter such as leaves, roots, and fruits. They also devour rotting remains of other insects, including their kin. When not invading dwellings, camel crickets are found in tool sheds, damp wood piles, beneath upturned wheel barrows, or in cool dank spots such as a leafy redoubt behind a rubbish bin along the shaded, northern aspect of my foundation. In addition to engendering the “yuck” response, they are occasional pests because they nibble stored fabrics. In tool sheds their fecal remains stain wood and tools.
Fecal spots left by camel crickets create a foul ambiance to the interior of a tool shed.
Their annual home invasion begins in force late in summer and early autumn and they favor 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 including 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 of siege 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. Recently, as I chased one sartorial visitor around the bath tub, 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 slam-dunking at a rim 60 feet above the court!
Sticky traps like this will snare not only cockroaches but camel crickets as well.
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 and place them outdoors. Or as one cricket aficionado noted, they make excellent fish bait. Fortunately, when wrangling these leapers I have a long-handled insect net that gets the job done. If you are armed with vacuum cleaner or jar, I wish you luck. 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.
A trip to the tool shed becomes a little creepy when Asian camel crickets come to visit.
With the revelation of Asian camel crickets in the basement and Asian stink bugs about to enter my attic, it only seems fitting to order some Chinese food for dinner.
References
Thanks to Megan Cloherty and WTOP for providing the inspiration for this episode. The wonderful article “Too big to be noticed: cryptic invasion of Asian camel crickets in North American houses” by Mary Jane Epps, Holly L. Menninger, Nathan LaSala, and Robert R. Dunn was used as a reference for this story.
To learn more about camel crickets, please visit the following web sites:
http://dx.doi.org/10.7717/peerj.523
http://www.ces.ncsu.edu/depts/ent/notes/Urban/camelcrickets.htm
http://www.wtop.com/109/3694474/How-to-rid-a-basement-of-invasive-species-of-crickets