This tale was originally published by Loret T. Setters on October 13, 2013 at the defunct national blog nativeplantwildlifegarden[dot]com. Click the date to view reader comments and find working links to other stories.
I was taking my routine morning walk and headed back toward the pond. As I approached the one spot where I have a good view of the turtles and fish, I heard a loud buzzing. Something large, VERY large circled away from me, but quickly came back and landed on the ground.
How fun that it was to watch a Great Golden Digger Wasp (Sphex ichneumoneus) bringing a katydid to provision her nest in order to lay her eggs. The prey may have been a grasshopper, but, at any rate, it was some sort of Orthoptera, an insect order that also includes crickets in addition to the other two. Let’s just say jumping things.
This prey will serve as the food for the larvae that hatches and will grow into future Sphex wasps. Momma Wasp stings the prey to paralyze it with toxins. She then flies, as this one did or if her prey is too big or heavy drags it to the nest. This prey was much larger than the wasp itself but it still managed to fly it in. Makes you wonder if katydids are hollow.
Prior to the capturing process, a nest is painstaking dug in a sunny location with Momma carefully digging out grains of sand or dirt, carrying it to the entrance between her arms and then flipping it underneath her body and between her legs. Sounds like the digging method my Irish setter uses. I’m betting it is a long process since I read that they create several tunnels off this main deep entrance.
These wasps have a fascinating provisioning behavior. I was surprised to see her crawl into the nest leaving her jumping friend lying at the entrance. Of course since it was paralyzed it didn’t have the ability to escape on its own. Good for me as I was able to get a photograph or two, but I thought it odd that she would leave it exposed where another critter (looking up to the sky…no, not me) might come along and scoop it up as a ready-made meal. Apparently this does happen, with birds being the likely suspects.
Research reveals that if the prey is moved further away (mean researchers they are) when Momma comes out, she will drag the prey back close to the entrance and once again pop in to check the nest prior to bringing the prey inside. She will do this numerous times (REALLY mean researchers they were) despite the fact that it is the same exact prey that she initially caught.
The only thing I can think of is that she is so wary that something might infiltrate her house, even in the short time it takes to bring the prey back a few inches that she feels the need to double check that all is in order. Rather paranoid if you ask me, but hey, I’m not in the wasp business, so what do I know. Heck, many humans have neurotic behavior (think checking two or three times to see if the windows are locked). If Momma wasp wants to be super-careful with her nursery seems like she should be nominated for a mother of the year award rather than cast in the light of needing therapy.
Since the only prey of the Great Golden Digger Wasp are what one might consider pest species, and since it pollinates, it is definitely high on the beneficial list.
Another prey-dragging wasp is in the Pompilidae Family: the Spider Wasp. A while back I observed what I believe to be a Blue-Black Spider Wasp (Anoplius spp.), Wolf Spider in tow. A very BIG spider; much larger than the wasp itself. All these wasp-types must work out.
This tenacious flying insect walking along the ground with its prize also fascinated me. Now that I think about it, I’ve seen more spider wasps crawling around the ground looking like they are on a mission, than I have seen flying around the flowers. Yet another wasp that has a set behavior in life.
Wasps are important players in the garden with their pest control and pollination duties, so don’t grab the bug spray out of fear. Let them be to do their jobs and sit back to enjoy the show.