Showing posts with label Yikes. Show all posts
Showing posts with label Yikes. Show all posts

Thursday, August 2, 2012

Holy Cow...a Cicada Killer Wasp!

We saw our first ever Cicada Killer Wasp this weekend. Rick watched him hanging out by the ash tree and called me over to take a look. When I caught sight of him "Yikes" was the only thing I could say. He was a big wasp. Really big. Almost two-inches-long big. How on earth had we never seen one before...it was huge! The wasp was lapping up sap near the base of our dying ash tree (the same tree from this post) and didn't seem to mind us looking on. We watched it for a while, but then I ran in and got my "Kaufman Field Guide to Insects of North America." It only took a few minutes to identify him--it's not hard to find a wasp that's close to two-inches long...

Cicada Killer Wasp (Sphecius sp.)--a very large wasp measuring almost 2 inches
Cicada Killer Wasp (Sphecius sp.)
This looks like an average-sized wasp, but when you consider he was about 30 feet up the tree, and I could still focus in on him, you start to get an idea of his size. He's nice and colorful too...with orange-ish legs and reddish-eyes, not to mention the yellow and black stripes on his abdomen.

Cicada Killer Wasp (Sphecius sp.)--a very large wasp measuring almost 2 inches
...but don't get too worried. These gentle wasps are not aggressive. The males have no stingers, and the females really only like to sting Cicadas. They will sting humans, though--but only if they feel threatened or you try to hold them down.
Cicada Killer wasps live up to their name. The females are hunters, and when they find a cicada, they sting it, paralyzing it with venom. They then carry (either flying or walking) the paralyzed cicada to a burrow where they have dug tunnels that end in cells (up to 16 cells per burrow or nest). They drag the cicada to one of the cells and lay a single egg on it. The egg hatches out and the grub-like larvae eats the cicada alive as it grows. (Source, "Kaufman Field Guide to Insects of North America," by Eaton and Kaufman, pg 336.) I spent some time watching two wasps fly around in our tree, but never did witness a cicada take-down.

Cicada Killer Wasp (Sphecius sp.)--a very large wasp measuring almost 2 inches
Yellow markings on the black abdomen of a Cicada Killer Wasp.
Cicada Killers like to build their nests in loose soils. The drought has created a few sandy spots on some of our hills in the front yard. We think we know where one of the burrows is. I read the wasps can displace up to a pound of soil while excavating the tunnels and cells, and the holes often look like they could belong to an animal. I'm going to watch for more and hopefully get some better photos.

Cicada Killer Wasp (Sphecius sp.)--a very large wasp measuring almost 2 inches
The Cicada Killers loved the sap leaking from our ash tree. Adults live on nectar and pollen from flowers...and sap from trees. They don't eat the cicadas, only the grub-like larvae do. 

exoskeleton of the cicada nymph after molting
The exoskeleton of the cicada nymph. I wonder if this cicada survived after molting, or if the Cicada Killer got him!
To learn more about Cicada Killer Wasps, click here for information from the University of Kentucky.