FORT IRWIN, Calif. — Few animals can give you the heebie-jeebies like tarantulas. These creepy crawlies, with their long legs and hairy bodies, can make your neck breakout in goosebumps, but this spider doesn’t deserve the fear it inspires. In fact, tarantulas are some of the least-aggressive arachnids in the world. A traveling tarantula is usually searching for a new home or a mate and is uninterested in humans. If threatened, a tarantula will raise up their front two pairs of legs to look bigger and show off their fangs, but tarantulas are unlikely to bite unless handled roughly. Moreover, a tarantula bite is not lethal to humans and is typically not worse than a bee sting. As a secondary method of defense, tarantulas found in America have barbed and prickling hairs on their abdomen that they will brush into the faces of threatening animals. The hairs will cause temporary irritation to the nose, mouth, and eyes, allowing the spider to get away. Like other spiders, tarantulas hunt by using venom to paralyze their prey. Rather than spinning webs to capture prey, tarantulas are “ambush predators” and they hunt using burrows dug in the ground. The burrow entrance is lined with a web trip wire system that will alert the spider when prey is near. Tarantulas will eat anything that is the right size: insects, other spiders, lizards, and even small rodents. Although male tarantulas have a relatively short lifespan of less than ten years, females can survive as long as 35 to 40 years.
Tarantulas belong to the Class Arachnida, a group of arthropods that include other spiders, scorpions, ticks, and mites. A common species on Fort Irwin is the Mojave Desert tarantula (Aphonopelma mojave). This tarantula creates a tower-like mound from pebbles, sand, and plant material around the entrance of their burrow. They will use webs to hold the assortment together and support the structure. In autumn when the temperature cools, male Mojave Desert tarantulas will leave their burrows in search of a mate. When a burrow of a female is found, the male will lightly tap at the entrance to make his presence known. The female spider may not acknowledge the male, but if chosen, the male must be careful. Female tarantulas have been known to eat the readily available source of protein (a.k.a. the male tarantula) after mating. Female tarantulas will lay hundreds of eggs which take six to nine weeks to hatch.
Next time you encounter a tarantula, do not fear. Take some photos, wish the spider well, and know that these fun creatures are an important and unique part of the animal world.
The Fort Irwin Directorate of Public Works (DPW) has wildlife biologists on staff who are trained to safely manage wild animals creating a safety hazard or nuisance. If you have a wildlife concern, you can reach the on-call wildlife biologist directly by dialing 619-288-8883. If you have any questions about the environmental department, the DPW front desk can be contacted during regular business hours at 760-380-5044. Any issues pertaining to domesticated pets should be directed to the Animal Control Facility 760-380-8564. To request insect, rodent, or dead animal removal, contact All-Pro Pest Control at 760-380-4099.