Camel Crickets 101
Meet the Harmless Camel Cricket or Spricket
How many times have you gone down into the basement, into the back yard, or into your garage and found a hopping creature that looks like a spider and has the legs of a cricket? (usually this is followed by screaming or impolite words). This leaping creature is the camel cricket, a nocturnal insect in the order Orthoptera and the family Rhaphidophoridae (Rap-he-doe-fore-a day). They are light tan and brown, about 1-1 1/4" long, and they don't have wings (so no worries about flying). Camel crickets are related to cave crickets and occur across the US, all continents, and most islands. They like moist, dark, and damp environments which explains why you find them in garages and basements. The most common species here in the US is the Spotted camel cricket but researchers are finding that the Japanese camel cricket is also starting to invade our homes too.
Why Do These Crickets Look So Creepy?
Part of what makes camel crickets so scary is that they physically look like big spiders, they come out at night, and hop when startled. This is why they are also commonly called "Sprickets" or spider-crickets. Camel crickets have six very long legs, a curved hump back, and their large drumstick shaped hind legs make them good at jumping. Because of their relationship to crickets that live in caves it's thought that camel crickets don't have very good eyesight so they rely on their two super long antennae to feel, sense temperature (thermoreceptor), and navigate their dark surroundings. To defend themselves they respond to threats by leaping at them in order to scare away the possible predators (and it works well for humans!).
Do Camel Crickets Bite?
Although they look like big spiders they're actually crickets and they don't have fangs or the ability to bite. They have chewing mouth parts and eat just about anything, like a goat. Camel crickets are omnivores and will eat fungus, plant matter, insects, and even fabric or cloth. This is why they're considered household pests.
Do Camel Crickets Make Sound?
Camel crickets don't have the ability make sound, or to stridulate (st-rid-U-late), like their cousins the house crickets, which make sounds by rubbing their wings together. There's something good to be said about quiet house guests even if they look creepy.
How Do You Tell Males From Females?
Like all crickets camel crickets lay eggs. To lay their eggs the females have an egg depositing tube called an ovipositer (egg-depositor) on her rear. In the picture below you can see the long curved ovipositer along with two other thinner projections that are used to sense wind, temperature, and humidity. She uses these to be able to find just the right conditions for laying her eggs. Some people think the ovipositor is a stinger, but it's a harmless egg laying tube.
If The Male Camel Crickets Don't Call How do They Attract Females?
In the Journal of Insect Behavior scientists Haley and Gray discovered that camel crickets appear to use chemical scents or pheromones. Insects like crickets breathe through very, very, very tiny tubes that line their abdomen. Researchers put male camel crickets on paper towels. Some had their breathing tubercles open and some temporarily blocked. It was theorized that the male released pheromones (chemical smells to attract females) through the tubes. Indeed, female camel crickets were strongly drawn to the paper towels that had previously had the males with open tubercles or tubes.
In their original work in 2011 Haley and Grey published findings in the journal of Ethology about how some male camel crickets actually have built in spikes on their large back legs that they use to duke it out, male to male, when fighting for a female. These same spikes are apparently also used for grasping the female during mating especially with non-virgin female crickets that might be a bit less than enthusiastic.
Are Camel Crickets Good For Anything?
Mostly camel crickets are considered household pests because of their goat like grazing on plants, fabrics, and items in basements and garages. When it's cold they tend to congregate together, which may also hold potential for more damage.
Unfortunately (more bad news) North American camel crickets are also what are called intermediate hosts (Pterygodermatites peromysci) for nematode parasite that infects white-footed mice and deer mice. Some of these mice already have nematode parasites in their guts. The nematodes transfer their eggs into the mouse feces when the mice defecate. These infected mouse fecal pellets are then eaten by the camel crickets. Inside the camel cricket's gut the nematode develops to maturity. When a mouse eats the cricket the adult nematode then infects its guts and so on. Research suggests that this parasitism may affect the population of white footed mice and deer mice, which in turn may affect food availability for predators that rely up on them for food. Fortunately the mouse parasites (nematodes) don't affect humans directly but they have the potential for destabilizing local food webs. For more information check out this article from the National Center for Biotechnology Information.
Don't discount the camel cricket though because it's a major food source for insectivores like voles, moles, and other nocturnal animals.
Join the Camel Cricket Census and Learn Which Species of Camel Cricket You Have In Your Home
If you'd like to know the exact species of camel cricket inhabiting your home then check out this great resource guide by the Department of Biology at North Carolina State University: http://crickets.yourwildlife.org/species/. On their website you can find pictures for identification and more detailed notes on their blog about the differences between the Japanese v. American camel cricket. You can also join their citizen science survey of native v. invasive camel crickets and their distribution. This is a great way for kids to get involved at home, and could be a useful assignment for teachers and outdoor educators.
HELP! I Have Camel Crickets
As mentioned earlier, camel crickets are omnivores that will eat about anything. They favor easy to graze on vegetation, which may include fungus growing in damp places such as basement walls, damp floors, and in the cracks of unsealed rooms. Even worse, if you find them in large numbers their feces (frass) can also stain floors and walls and the crickets are an attractive food source for mice! I'm not a big advocate for killing anything, after all they were probably there first but humans built a nice house in their habitat. If you find yourself needing to remove an infestation you could try the following:
- Seal up floors, windows, and doors where they might be coming in. Also secure weather stripping.
- Dry out basements and damp areas. A dehumidifier should help.
- Shed light on dark areas for extended periods of time if possible.
- Remove leaf litter, vegetation, fungus, and other food sources.
- Seal up cloth items, bags, and other objects in garages and basements in plastic containers and make sure they are stacked away from walls.
- Do not stack firewood near the house, and make sure bushes and shrubs are also away from the house.
- For those interested in natural defenses you can use cedar pouches and oils in solution. Cedar is a natural fungicide and insecticide. The same is true of tea tree oil and citronella.
- Peppermint oils and sachets, often used for mice as well, also work for camel crickets.
- I'm not a big fan of the sticky boards that most pest control places advocate, but they are an option on the market. I find them rather cruel, though perhaps no less cruel than vacuums or cats.
- If all else fails you may have to call in an exterminator.