Saturday, July 05, 2014

Facing the Spider Wasp Gauntlet

For the last 5 summers or so, generally during June and July, I find myself facing a gauntlet of hovering, blue-winged, red wasps every time I pass through the opening between our breezeway and the back yard.

Wasps are my "phobic animal", so it takes a bit of courage every time I venture this way, usually to take the trash or recycling out or to water plants.  I've never been stung or even threatened with stinging, despite going through this gauntlet many times, but the hovering wasps give me an adrenaline jolt nonetheless.

Last summer, I finally figured out what these wasps were and what was going on, which I blogged about in "The Wasp Version of Baby Bottles":  these are (solitary) spider wasps, probably of the genus Tachypompilus.  That means my gauntlet of hovering wasps are a bunch of males, checking me out to see if I'm a female wasp in need of their fertilization services.  Since they have no egg-laying equipment, they have no stingers and couldn't hurt me if they wanted to...a biological pronouncement that I am, nevertheless, NOT going to test!

Interestingly, two weeks ago when I visited fellow Master Gardener Sid's home (which is about 5 miles from mine "as the crow - or wasp - flies"), I saw that he and his wife have a population of the same species of wasp.  Their spider wasps also make their nest cells between the finished concrete surface of their porch and the rougher foundation, just like mine.  Sid and Sandy, too, have watched the female wasps bring back paralyzed spiders to provision those nest cells for their eggs/young.

Occasionally I get a glimpse of a female out in the garden, prowling for her spider prey.  They move very quickly and, like most predators, are well aware of my presence.  They hide as soon as they possibly can, even while continuing to hunt, which makes photographing them a real challenge.  I usually see them on the ground, but that may just be a function of when I'm most likely to be still enough to notice them, which is when I'm weeding.

The more I learn about wasps and bees, especially about our native solitary species, the more interested and enamored I become.  Unless you try to capture a female and hold her, they are extremely unlikely to sting.  These wasps are important predators, helping to maintain balance between plants and plant-eaters and predators in our gardens, as they provision their nest cells with spiders or caterpillars or grasshoppers or cicadas.

And speaking of cicadas, I'm hearing the first few males warming up now in the afternoon.  The summer chorus is about to begin...and the cicada killer wasps won't be far behind.

Cicada killers are huge, frightening looking wasps that nest in bare dirt, often underneath decks.  Just as in "my" spider wasps, the males patrol the nesting area, trying to find females to mate with - but despite their scary looks, they have no equipment they can use for stinging.  The females can sting, but they are inevitably too busy hunting for cicadas and lugging them back to their nests (which they alone dig out) to bother with humans nearby.  Just don't try to pick one up....

In general, I'd say the spider wasps are around for about 2 months, and the cicada killers generally are seen for only about a month.  So if you find yourself sharing your garden with these winged creatures, have patience, keep your eyes open for the hardworking females, and practice conquering your fears!  Your yard will be healthier for it.


Gardener on Sherlock Street said...

I have learned so much about the "scary" insects from you.

Gaia Gardener: said...

Thanks, GonSS. Hope it's been interesting!