On a recent trip to western Kansas I kept noticing a fast flying, large insect moving erratically across the short grass prairies we visited. They wizzed by so quickly I could not get an ID. The sound of their wings and the sheer size of them was intimidating, and I was determined to figure out what these giants of the insect world were. It took two days, several trips to the prairies, lots of hiking, and multiple fly-bys, before one finally landed long enough for a positive ID. It only took two seconds to recognize it as a tarantula hawk wasp! This particular insect is one I had hoped to see on our trip and was thrilled to have been allowed the privilege. After experiencing a lifer insect, I was not to be stopped at just seeing one, I wanted to see one in action! Every trip into the prairie for the following three days I expressed my wish to see one grab a tarantula.
On our last day in the area we visited Smoky Valley Ranch, owned and managed by the Nature Conservancy. This working ranch is over 18,000 acres of habitat for bison, prairie chickens, lesser eared lizards, and much more. We no sooner entered the prairie on the primitive trail when I began spotting tarantula hawks. I saw dozens of them, and I kept telling myself...where there are tarantula hawks there are tarantulas! It was nearing sundown and before it got too dark to see, I headed back to the car. I had my eyes pretty much glued to the trail in front of me seeking insects to photograph before I lost good light...when low-and-behold, right at the edge of the trail not 30 feet from the car sat a tarantula! Several tarantula hawks were flying in the area and I couldn't help but wonder if one would spot this spider out in the open. It was only after several minutes passed that I realized this tarantula was not behaving right. It was not moving. I squatted down to get a closer look when out of a hole behind it appeared a tarantula hawk! This tarantula had already been discovered by one of these large wasps!
Tarantula Hawk Wasps are a solitary wasp belonging to the family Pompilidae. There are 133 known species and probably more waiting to be discovered. There are two genus' Pepsis and Hemipepsis. Two of the most commonly encountered are P. grossa and P. thisbe. They look similar and can be difficult to differentiate one from the other. P. grossa have blue bodies with reddish antennae, that P. thisbe lacks. I was sure the one pictured here was P. thisbe, but cannot be 100% certain.
These wasps are huge! They can reach lengths over two inches. As adults, both males and females nectar at a variety of flowers, but the offspring need a diet of protein to develop. Like their name suggests it is tarantulas they are seeking. These wasps fly over tarantula habitats scanning the areas for tell-tale signs of prey. Tarantulas know to avoid these wasps, but escaping a vigilant huntress is not always easy. Once the wasp has located a tarantula she will sting it between the legs which paralyzes it quickly. If the wasp entered the burrow of a female tarantula investigating it for prey, she may use that burrow for her brood chamber...or not, she may move it to a nest chamber she previously created. If she locates a male tarantula on the move, she will drag its paralyzed body to a burrow she created herself. Whether she chooses to relocate the tarantula or utilize the lair of the unfortunate spider, one thing is certain once the spider has been stung its fate is sealed. Using their long legs with special hooked claws they are able to drag these large, immobilized spiders surprisingly long distances over clumps of grass and other obstacles.
The female wasp will lay a single egg on the abdomen of the tarantula, cover the chamber and leave. When the egg hatches the little wasp larvae will burrow into the abdomen of the provided protein packed spider. The haemolymph, or blood-like fluid, is usually the first to be consumed, then gradually tissue is consumed avoiding vital organs until the very final stages of development for the larvae. Once the larvae pupate the spider will succumb to its unfortunate experience. Eventually the adult wasp will emerge from the abdomen of the tarantula and the cycle starts all over.
If this sounds like the stuff of nightmares, it is, at least for the tarantula.
With large wasps, come large stingers, and tarantula hawks have some of the longest in the wasp world, P. grossa is reported to have a stinger that is 15/32 of an inch long!!! Only the females have stingers, males do not. Their sting is reported to be one of the most excruciating experiences in the wasp world. Thankfully, these solitary wasps are docile by nature and are only prone to sting if sufficiently harassed. If you are crazy enough to harass a wasp this large, maybe you should be stung. With such a powerful defense mechanism onboard, very few animals will chose these wasps as a meal. I read roadrunners will eat them, they must be really good at not getting stung. Stings are not considered medically important, you're just going to hate life for awhile. If you are allergic to stinging insects then immediate medical care should be sought.
One researcher described the pain as "immediate,excruciating, unrelenting pain that simply shuts down ones ability to do anything but scream!"
An entomologist by the name of Justin Schmidt came up with the idea to create a sting pain scale. He allowed himself to be stung over 1,000 times and compared each sting with previous ones and gave each a rating based on intensity, duration of pain, etc. On a scale of one to four, he ranks honey bees as a two, with a four being almost unbearable in pain. Guess where tarantula hawks came in? You guessed it....a 4!
The sting of a tarantula hawk wasp is ranked #2 in pain level only after the bullet ant!!
Fortunately, for humans these wasps typically pay no attention to us as we venture into their hunting grounds. This is one wasp, however, I would not recommend swatting at with your hat. The pain, said to last about 5 minutes, would feel like hours, as you scream in agony.
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