The RoVing Naturalist
By Dennis Prichard
If you’ve been a snowbird in the Southwest U.S., you may have seen a rather dauntingly huge wasp, black with gold wings, flying low across the desert floor, sounding much like an aircraft.
This is the tarantula hawk wasp, and its story sounds like a horror movie.
An adult female wasp is cruising for her favorite prey, tarantulas, those large hairy spiders that lumber along usually after heavy rains have washed them out of their holes. The wasp has a hole of her own all ready for provisioning.
She sees the large spider and lands in front of it. The spider has poor eyesight, but seeing a blurry figure dancing around causes it to go into defense mode: It rears up on its hind legs trying to look ominous. The wasp is quick to grab the spider’s large fangs with its front legs, and then she thrusts her abdomen and stinger at the spider, trying to penetrate its tough outer exoskeleton. At the point where the spider’s leg meets the body, a gap allows the stinger to go in and soon the wasp’s poison takes effect.
However, the venom does not kill the spider: That would be counter to its purpose. Instead, the spider is only paralyzed.
The wasp drags the limp victim underground, away from the drying sun and wind. Properly positioning the sleeping giant, the wasp then deposits one small egg on it and then departs, covering the larder with dirt. The egg hatches and the young pupal wasp starts eating the massive food bank in a manner that keeps the spider alive as long as possible so it does not decompose before the meal is over in several weeks.
When finished, the little pupa encapsulates itself, further protecting it from any temperature fluctuations. When it hatches the next summer, the now-adult wasp drills out of the burrow to start the next generation, and the dance of life and death goes on.
If you see one of these winged wonders, give it some space. Although the sting can be quite painful, don’t fear them as these solitary wasps are much less aggressive than the colonial paper wasps and hornets. As with most animals in nature, if you give them a chance to get away, they usually take it. And at the next horror movie you see, judge if it’s as scary as the real life struggles under the desert floor.
Dennis Prichard is a retired park ranger. He’s worked and studied wildlife at many National Parks and Wildlife Refuges including Carlsbad Caverns, Mammoth Caves, the Everglades, Sequoyah NWR in Oklahoma, Sevilleta NWR in New Mexico, and Isle Royale National Park, to name a few. He travels in a fifth wheel with his wife and dog, a Labrador named Cricket.