Eastern Cicada Killers

Every summer, about this time, little piles of dirt appear in the lawn along one side of the driveway.  The other morning when I went out to get the newspaper, I saw what must have been 50 really large insects chasing each other around in circles, about one foot above the lawn.  They are large brown insects, with black and yellow abdomens and they are killer wasps.  I looked them up.  They are called Eastern Cicada Killers, and they go around and sting Cicadas, which paralyzes them. After paralyzing a cicada, the female wasp holds it upside down beneath her and takes off toward her burrow; this return flight to the burrow is difficult for the wasp because the cicada is often more than twice her weight. A wasp will often lug its prey up into the nearest tree, to gain altitude for the flight to the burrow. After putting one or more cicadas in her nest cell, the female deposits an egg on a cicada and closes the cell with dirt.  Whew!

I have no idea of the population that lives under our lawn.  The good thing is, that the Cicada Killers will not sting humans, unless the insect is handled roughly.  I am sorry I was unable to get a photograph of one of the wasps.  They never stopped and rested anywhere.