One of the most misunderstood insects, this strange looking creature has been called many names during its presence in North America and Mexico. Early Native Americans referred to the Jerusalem Cricket as the ‘Old Bald-Headed Man’ or the ‘Red Skull’ because of its uncanny humanoid head. Today these insects are found along the west coast of the US and Mexico and often referred to as ‘Potato Bugs’ despite their preference for other roots.
Though sightings of the Jerusalem Cricket are actually quite rare, once spotted they are hard to forget. Although they bear the name of cricket, these insects are actually in a different family altogether. Unlike other crickets, the Jerusalem is wingless and has an abnormally large head that many believe resembles a human head. However, despite its alien look, the black and tan banded insect is actually not harmful or poisonous and will only bite if provoked. Entomologists are still learning about the Jerusalem Cricket, but many believe that the insect may be more helpful than harmful in its environment. According to the Nevada Division of Agriculture, the Jerusalem Cricket has not officially been deemed a pest or beneficial insect at this time.
Jerusalem Cricket Identification
An adult Jerusalem Cricket will reach 2 inches in length (30-50mm). The large head of the Jerusalem Cricket is its most distinguishing feature because it is so disproportional to the rest of its body. The ‘humanoid’ head of the Jerusalem is superbly adapted to support the equally large jaws that give the Jerusalem its digging power. The powerful jaws and mandibles not only allow the Jerusalem Cricket to burrow deep into the earth, but also strip off roots and tubules for a constant food source. Given the chance, the Jerusalem will consume other insects. Generally these insects have an orange and black banded body with a tanned head and under abdomen though shades can vary. Carrying no poison, the Jerusalem is not lethal in any way; however, they do give nasty bites if provoked by predators.
Jerusalem Cricket Habitat
Jerusalem Crickets love damp places. Ideally they will reside burrowed in moist soil or in manure heaps. Any large object can offer them protection and added precipitation is also sought after. Jerusalem Crickets get their nickname ‘Potato Bug’ from the fact that they are often found buried in potato or other crop fields. During the fall and winter months, these creatures will go into hiding and will generally not resurface again until planting time. You may find a few Jerusalem Crickets in the garden, but don’t be overly alarmed, they have not been known to harm crops.
Jerusalem Cricket Predators
Being a nocturnal insect, the Jerusalem Cricket has few natural predators. If the cricket does venture out during the night it does become prey to animals such as the owl (particularly the screeching owl), badgers and other nocturnal rodents.
Myths about the Jerusalem Cricket
Many might think the Jerusalem Cricket’s name is a bit deceiving, and they would be right. These insects did not originate or currently live in Israel. The legend surrounding this name suggests that a Franciscan priest was living amongst the Navajo tribe where the Jerusalem Cricket is common. The Navajo called this insect the ‘Skull Insect,’ but the priest misinterpreted the name to mean ‘Skull Hill.’ The priest took this name and mingled it with Christianity by using the hill where Christ died, Golgotha, which being interpreted means ‘skull.’
Jerusalem Cricket Communication
As previously stated, the Jerusalem Cricket is not, in fact, an actual cricket and therefore does not communicate like one. Insects in the cricket family (Gryillidae) generally communicate by rubbing their wings together or creating a hissing sound. The Jerusalem Cricket does most of its audible communicating during the mating season; throughout the rest of the year the Jerusalem will only make sounds if warding off harm. By rubbing its hind legs against the abdomen, the Jerusalem Cricket will create a raspy sound designed to put off oncoming predators.
If the Jerusalem does need to communicate to other members of its nest, the cricket will do so through vibration. Located directly beneath the knee on each leg is the subgenual organ. This complex tissue is thin and fan-shaped and specifically designed to emit and absorb vibrations through the ground. By sending and receiving these signals, the Jerusalem Cricket can effectively communicate over distances and through barriers.
Jerusalem Cricket Life Cycle
The mating season of the Jerusalem Cricket is distinguished by the change in communication. Instead of relying on vibrations to send messages, the Jerusalem Cricket will come on a little stronger as it emits a drumming sound to attract the opposite gender. Both males and females beat their abdomen strongly on the ground for a consistent drum sound. Although not generally aggressive towards humans, once mated it is not uncommon for the female Jerusalem to devour the male. Despite the males having larger heads and thoraxes, the females are just as strong and have a slightly bigger body.
After mating, the female will burrow 6-10inches underneath the earth (generally choosing a pile of rocks or logs to hide under) to create the nest. The nesting chamber is lined with a white, think material and will house the 1/8inch eggs. Once hatched, the Jerusalem Crickets will grow to full adulthood in a year and have an average lifespan of 2-3 years.
Jerusalem Cricket Control
The Jerusalem Crickets are not generally considered a pest problem. Spending the majority of their time underground, these nocturnal insects only roam on the surface during the evening or early morning and make their diet out of decomposing organic material. Although somewhat ferocious in looks, these crickets do not have large colonies and are only seen in small numbers. For the most part they will remain hidden until planting or harvest season when their colony is upturned.
Although they are not proven pests, if you do find them in large numbers or want to prevent the possibility of Jerusalem Crickets then there are a few suggested means.
Natural:The best and most common way to get rid of Jerusalem Crickets is by simply removing their habitat. Below are a few simple ways that will deter the insects from making your home, garden or field their home.
Clear away any large, natural objects that give off additional shade or hold in moisture (rock piles, logs, etc.)
Reposition any large piles of moist substances (i.e. mulch or manure). Jerusalem Crickets will not generally cross large dry spaces, so create a distinctive gap of concrete or dry ground.
Set your sprinklers to be turned off during the day; the drier the ground is the less likely they are to surface.
Place weather stripping on doors and windows to prevent the crickets from venturing into the house during fall and winter.
Man-Made: If you do feel that these insects are posing a threat to crops or that there is an infestation the suggest methods are baiting and trapping. Insecticide should be used as a last resort with these crickets.
Keep in mind that having these insects in your garden or crop field is not necessarily damaging. Jerusalem Crickets may look abnormal, but their eating habits are consistent; they feed on already dying material and may even consume other harmful insects in your crop.