Activity is starting to heat up in my garden as the blistering heat of August in Florida cools down. August is generally a quieter month for wildlife activity as everyone hunkers down to take a time out…rather like winter break up north when it gets to cold to do anything.
With September upon us, there is a dizzying flurry of pollinators flitting here and there. I noticed a rather slim “something” envelop a bloom of the Bidens alba. It had long lanky legs and I thought perhaps some sort of mantid or grasshopper as it seemed to climb from flower to flower. Of course the coloring was all wrong for those types of insects, so I was intrigued to find out who my new visitor was.
Lo’ and behold, as I crept closer I saw this Sphecid Wasp drinking in the sweet elixir of my favorite Florida native wildflower. I had seen this type of wasp in the past, but not often enough to be able to put a name to it. A check of my resources and I learned it is Ammophila procera, a Thread-waisted Wasp. Given that skinny midsection, aptly named.
This particular species is one of the “digger” wasps, so-called because they dig tunnels into the ground to nest. As I’ve reported in the past, I’ve encountered similar species watching in awe as a Great Golden Digger Wasp (Sphex ichneumoneus) dragged it’s large katydid prey below ground.
My latest wasp visitor uses caterpillars as the host for its larvae. Now, before you get in a tizzy worrying about your precious butterfly caterpillars, don’t be alarmed. This species has a taste for moths with documented use of White-dotted Prominent (Nadata gibbosa), Variable Oakleaf Caterpillar Moth (Lochmaeus manteo) and one that I find at my place, the Morning-glory Prominent Moth (Schizura ipomoeae).
These species of caterpillars are often considered “pests” because they defoliate trees. Keep in mind that each insect has a roll to play in the big scheme of things but most humans will agree it is a lot easier to accept the disappearance of caterpillar that ultimately is somewhat dull in the color department as an adult over seeing a chunky monarch caterpillar disappear.
It was fascinating to read about the Thread-Waisted Wasps nest building habits. They drag their paralyzed bounty backward into the tunnel, laying an egg on a particular segment of the host. Interestingly enough, they make provisions for temporary closure of the entrance if they need to leave briefly, with anecdotal evidence of the use of pebbles, sand spurs, an acorn and even a rabbit pellet as a entry plug.
The wasp seals it up permanently when everything is in order to her satisfaction. This part of the lifecycle takes approximately 33 days over all: eggs hatch in 2 days, larval feed and spin a cocoon after 5 days and the adult emerges 26 days later.
Even more fascinating was a time lapse video I found of the nest provisioning procedure.
Since solitary wasps aren’t necessarily aggressive, welcome them and appreciate their important mission to pollinate and practice chemical free biocontrol in your own beautiful wildlife garden.
Dick Walton http://www.rkwalton.com/wasps.php
Observations on the Nesting Behavior of Digger Wasps of the Genus Ammophila
Howard E. Evans
American Midland Naturalist
Vol. 62, No. 2 (Oct., 1959) , pp. 449-473
Published by: The University of Notre Dame
Stable URL: http://www.jstor.org/stable/2422538
Title: Additions to the Knowledge of the Nesting Behavior of North American Ammophila (Hymenoptera: Sphecidae)
Author(s): Jerry A. Powell
Source: Journal of the Kansas Entomological Society, Vol. 37, No. 3 (Jul., 1964), pp. 240-258
Stable URL: http://www.jstor.org/stable/25083390