Saturday, September 27, 2014

Coastal BC Insects: Aerial Yellowjackets

Aerial yellow jacket nest on granite wall.
What's a summer BBQ without a few uninvited guests.  They come dressed in their yellow and black jackets, ready to dine on your hamburger. I'm not talking about Cousin Willy and his kin. I'm talking about those pesky yellow jackets.

Here in BC, the aerial yellow jacket (Dolichovespula arenaria) is a common summer visitor. Warm spring weather awakens mated queens from their winter roosts to find a likely spot for a new nest.  Aerial yellow jackets build large conical structures out of paper they produce by mixing saliva with chewed wood, much like paper mache.

The beginning of a new nest.
Typically nests last only one year. All of the activity ends when fall weather turns cold. Workers and males die off and only the mated queens survive. This makes late summer and early fall the worst time for encountering wasps. Their population is the greatest, and foraging for natural foods becomes more difficult. That's when they turn to human sources, creating conflicts.

Tools for a hidden nest under the cabin roof.
The good news is that yellow jackets aren't aggressive unless they or their nests are threatened. Accidental encounters can create dangerous situations. Individuals with allergies to wasp stings must take extreme care. Multiple stings can also cause medical emergencies.

John helping us get rid of a hidden nest.
This year we had two nests. The easiest to eradicate was on Wayne’s writer’s retreat boat. A heavy spray of wasp killer in the cool of the evening took care of them. The ones that moved into the space under our roof were harder to reach. John gave us a hand and went up a ladder, sprayed the spot with a heavy dose of poison, and sealed the opening with moulding to prevent future colonies.

Last week I did a stupid thing. A yellow jacket flew into our ocean crusing boat. He crawled behind a curtain, so I squished him between the window and cloth. During his death throes, he gave my finger a sharp sting. It was like a hot needle and the after effects included a prolonged stinging followed by a dull ache for about six hours. I stuck my finger in a bowl of ice water and used that treatment on and off for about an hour. I was fortunate. My finger didn't swell. You can be sure I'll think twice before I take on a yellow jacket again. -- Margy


  1. Yes those stings are awful. I got one a couple of years ago in my open weave plastic clogs on my toe. I have read that using one of those old copper penny helps ease the sting as well. Great photos!

  2. We had to take out a nest that was in our hedge beside our bbq earlier in the summer. We went for a walk last weekend and saw a nest 2 foot high by 1.5 foot wide, the largest I have ever seen. It was in a park with tape around it so humans wouldn't go near. They love the long hot summers.

  3. We have a new nest under the deck of the cabin where we can't reach it with poison. Because they will die off during the winter we are letting them go. Three poison applications from the surface hasn't phased them a bit. - Margy

  4. You poor thing! I have a cupboard, outdoors, with my pond equipment. I reached in, once, and didn't see it. It got me.
    I just removed two!!!!

  5. I tried some beer traps of my own, but only made the hive drunk and disorderly. I bought a wasp trap at Canadian Tire today. I'll see if that does a better job. It may be so late in the year they will die on their own. I just hope a new queen doesn't decide to start a nest under the deck next year. - Margy