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Spider Wasp Gestation

Spider wasps are named so because they attack spiders as part of their life cycle. These solitary wasps do not live in a nest like regular wasps, but in their own in burrows they dig into the dirt or sand with their front legs. Spider wasps typically are very large, with a black body and brightly-colored wings. Although they possess a painful sting, they are very unlikely to attack or sting humans unless provoked.

Mating and Nest building
- Male spider wasps are smaller than females, and practice what is called "hill-topping." They sit on tall points, like high vegetation, and watch for newly-hatched females to mate. Once spotted, male spider wasps will instigate mating and inseminate the female wasp. A pregnant spider wasp then will immediately begin nesting. She will dig a hole into the sand or dirt with her front legs large enough to accommodate her prey during the next stage of the spider wasp life cycle.
Hunting
- Once a nest has been dug, the pregnant female spider wasp will seek out prey, normally a large female spider, such as a tarantula. They often will be living in their own nests at this point, so a wasp will have to seek them there actively. The female spider wasp is strong enough to flip even a large tarantula onto its back, which will give the wasp the opportunity to sting the spider and paralyze it.
Egg Laying
- Once stung, the spider is permanently incapacitated. The female spider wasp then will drag its immobile prey back to the nest and pull it underground. Spider wasps occasionally will chew off the legs of large spiders if they have trouble pulling them into the nest. Once inside, the female spider wasp will lay a single egg on the abdomen of the paralyzed spider and then seal the nest with the spider and egg trapped inside.
Birth and Cocoon
- When the spider wasp egg hatches, the larvae will emerge and start devouring the immobile spider, feeding off its internal organs (literally eating it alive.) After feasting, the larvae will spin itself a silky cocoon and begin pupating inside the underground nest.
The Cycle Starts Again
- During the summer the pupae will continue to develop, and at the end of the summer the fully developed adult will emerge and dig itself out of the underground nest. Then, it will begin seeking a mate, and the fertilized females will dig another nest for them to overwinter. The pregnant females will emerge from this nest the following Spring to seek another spider host and begin the spider wasp life cycle all over again.

Insects & Science