Sunday, June 21, 2009

Stirring up a Hornet's Nest

Well, hopefully not! This time of year bald-faced hornets start making nests. Dolichovespula maculata is actually a member of the paper wasp family commonly found in North America. In Insects of the Pacific Northwest (Haggard & Haggard) they are described as social vespids.

If you can get close enough with getting stung, you will see their dark bodies with white face markings. They can also be identified by the way they fold their wings longitudinally over their abdomen while at rest. Plus, they have the distinguishing narrow (wasp) waist between the thorax and abdomen.

Nests are built in spring by new workers born from females mated the previous year. The first offspring are sterile female workers who chew wood into pulp to form a nest, sometimes reaching up to three feet in length. That sounds just about right for a hornet from a paper mill town like Powell River.

When I first saw the hornets there were two small half dome structures under a niche in our rock wall. After a few days, they were both incorporated into a larger nest with one opening at the lower end. Last year a nest was started under our cabin eves. I could watch them build it up layer by layer until our good friend John volunteered to knock it off for us. You can use wasp spray to kill them first, but if you wait until the cool of night they become somewhat dormant and the nest can be knocked off with only a little danger of getting stung. Unfortunately (for us that is) the rock wall nitch is in a place that we can't reach. We'll just have to more careful while swimming in our natural pool.

More sterile female workers are born throughout the early summer to tend the queen and feed the larvae. In late summer, reproductive males and females emerge to mate so the cycle can continue. In fall, after the first frost, all members of the colony die except for the newly mated females. They live through the winter to start new colonies in the spring. Maybe then we can remove the nest and maybe preserve it. Click here for some directions. But I think I'll forget about the relocation procedures. -- Margy

1 comment:

  1. Oh my, Margy!

    You just be careful. Oneday I'll write about my superbees!!!

    P.S. We are visiting Lake Superior. What a sight. I am amazed. Post about it later!