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The Tarantula Hawk Wasp's Potent Sting Stuns and Kills the Much Larger Tarantula

In Arizona we regularly see the B-52s of the wasp world, as the state harbors about a dozen species of tarantula hawk wasps. The females of some of these species measure among the largest wasps in North America, with robust 3-inch black bodies. Three inch-es may not sound like much, but when a tarantula hawk cruises our way, we definitely step swiftly to one side.

Most of us would move even faster if we knew that the female's sting (and only female wasps have stingers) hits a 3 on a 4-point pain-scale developed by entomologists unlucky enough to have been stung by a whole catalog of nasty insects. Those entomologists rated a honeybee's sting at a mere 2, suggesting that we would be well-advised to avoid getting zapped by a tarantula hawk wasp.

Fortunately, most of us will never be stung by one. This insect does not go out of its way to look for trouble with people. We would have to touch it to get stung, and not many of us would ever want to handle a tarantula hawk.

While we humans have little to fear from tarantula hawk wasps, tarantulas (and some other large spiders) have reason to be concerned. Female tarantula hawks like to exercise their stingers on these creatures, which they find in their bur-rows by poking about under bushes and rocks.

Tarantula burrows are uncommon, so a search typically takes a long time; Fortunately for a human to see a "kill" requires immense patience or a lot of luck. I have been lucky just once, when I noticed a female tarantula hawk walking rapidly in erratic loops on the desert floor. She reminded me of a bloodhound picking up a scent. The wasp eventually moved purposefully toward a small opening in the ground, which looked to me like the burrow of the pocket mouse. Within seconds of the wasp's entry into the "mouse" burrow, a large gray-brown tarantula popped out of a second open-ing a few feet away. The spider raced across the ground and climbed up a small shrub. As the spider stood frozen on a perch about a foot high, the tarantula hawk wasp charged out of the burrow exit. The wasp methodically moved forward, sweeping her large, curled antennae low over the soil as she tracked her prey.

Without hesitation the wasp marched directly to the shrub and climbed up to the spider. She then curled her huge abdomen under her head and jabbed upward, inserting her long stinger into the underside of the thorax of her seemingly helpless victim. It was over in a flash. The wasp's venom almost instantly paralyzed the tarantula before it could defend itself. The contest was so uneven, I felt sorry for the tarantula.

The unsympathetic wasp remained all business. After pausing for a moment, she began the job of moving the spider from the shrub. Grabbing the limp body by the base of a hairy leg, the wasp moved backward, pulling her collapsed prey behind her like a large sack of flour. She slid down from the shrub and backed across the ground, surmounting stones, weaving through grasses, over-coming every obstacle, until after many minutes of hard work, the tarantula hawk dragged her prey into a burrow.

I knew, without being able to see it, that the wasp would now lay an egg on the alive-but-helpless tarantula, then fill in the burrow with pebbles and debris, sealing the spider and (LEFT) Because they hunt the spiders to feed their young, these 3-inch wasps are known as tarantula hawks. (RIGHT) Agile and determined trumps big and hairy when these venomous titans of the insect world clash.

In wasp egg in the underground chamber a macabre scene worthy of Edgar Allen Poe.

Long after I left the site of the spider-slaying, the egg hatched into a wasp grub that feasted on the now-dead tarantula pro-vided by its mother. The grub became a pupa, which eventually became an adult, probably about a year after the egg was laid.

After burrowing upward to the surface, the newly emerged tarantula hawk wasp set about its tasks with the same skill its mother exhibited in finding and dispatching her prey.

If the emerging wasp was male, he headed to a nearby mountaintop to fight for a palo-verde tree territory. If a female, the wasp flew to a mountain-top to mate with a territorial male and then turned her attention to the local tarantulas, living up to her reputation as a great hawk of an insect.