One of the cooler (I think) Summer features of our yard are the Cicada Killers which appear each year about this time. They are a giant wasp (the one pictured above is about 1 1/4 inches long and perhaps 1/4″ thick) and live for about a month. Yes, really. But in that time, they demonstrate themselves to be extremely effective hunters of cicadas. By the time they are all gone, the lawn will be littered with dead cicadas that were unsuccessfully brought back to their nests.
The CK’s live in underground nests. They capture and paralyze the cicadas and bring them back to their nests, where they lay an egg on them. Their young then have the food to last them through the until next Summer, where the cycle starts over again. They also appear to be solitary insects, rather than a hive sort. While there may be many in the yard, they do not band together in a single nest. They are literally sprinkled around the yard, each with their own place. They engage in some pretty nasty aerial combat sequences with each other, though that’s typically only for the first few days after they first emerge from the nests.
The other interesting thing is when they return from the trees with a cicada, which are several times bigger than the CK, even as big as they are. The cicada is held between the CK’s legs and it’s obviously a struggle to get back to their nest with their payload. In fact, it typically appears that it’s all they can do to maintain any semblance of controlled flight. They try to get as close to their nest as possible. Once they’re on the ground, they can drag their prize for a bit, but don’t seem to be capable finding their nest if they are too far from it. If they don’t make it, they’ll abandon the cicada and get another one and try again. I’ve tried putting cicadas near a nest opening, but the CK’s won’t use them.
I’ve found that they are very passive where people are concerned. I’ve walked through a swarm of them in the yard (mowing the lawn) and they are content to let me pass. The one in the picture allowed me to get the camera within several inches of it without getting upset. I’m glad of that, as I wouldn’t want to be stung by one based on their size.