Looks like Yellow Jackets to me.
Looks like yellow jackets to me too. Their rear bodies are more narrow than those of a bee, with a definitely cinched waist, and they're longer, as least compared to the bees I've seen in my area. Their rear ends are very pointed as well.
Here's a really good photo of a yellow jacket:
Could you lay out one of the dead ones lengthwise to get a different view of it? Still I'm pretty sure you've got yellow jackets. Mean, nasty things they are.
I'm glad to hear you folks think they are yellowjackets too... I was feeling sort of guilty about the whole thing. Here is a closeup from last night's batch.
And the same two fellas from a different angle...
Thanks for the extra photos. I don't want to make you feel guilty, but the second photos look somewhat like bees as well as yellowjackets, so I'm not really sure at this point. As many photos of both as I've seen, it's still hard to tell the difference from photos.
I think I'd try to find an agricultural extension service to identify them so you can rest easy.
Garden Sprite, that has been on my to-do list since last week! I had to get a second (fresher) specimen, and finally made it to the Penn State extension office today before they closed today. Turns out these are yellowjackets (whew!), just as you all thought. No honeycomb in the wall to worry about.
Thanks to Redoverfarm's suggestion, I estimate I've removed close to 400 bees already, finding progressively less behind the duct tape each evening. Penn State advised that such a large number would be normal for yellowjackets given this time of year. They agreed with the pesticide-and-duct-tape approach, and also suggested poofing Sevin Dust into the hole, or in a baggie taped over the hole (the bees would get covered in it as they tried to get out toward the light). I've got my screen and silicone ready to use as the population dwindles. In a few days I hope to be able to post a pic of the covered hole (provided I don't make a mess of it!).
One more thing the entymologist offered was that by November the frost should kill any remaining bees, but since they are in the wall, this may protect them. The queen, she said, would normally haved survived the winter to relocate and begin a new hive in the spring. So I guess I'll have to keep an eye on things through next spring to be sure the problem has been fully resolved by the pesticide.
Glad the issue of the insect ID is resolved, and glad they weren't bees. I kept thinking as well that I've never seen bees in house cavities, but then I'm not an entomologist and am not that familiar with their culture.
400 yellowjackets is a lot of nasty stingers! You really are lucky you weren't stung.
Looks like Redoverfarm's advice was right on point. Glad it worked so successfully for you.
I don't recall without rereading my posts whether I suggested this, but you might also stuff a rag saturated with bleach into the cavity to help eliminate the queen. In such a small space, the odors would I think overwhelm the insects' breathing capacity. The only concern would be whether or not the odors would penetrate into the house, depending on any inroads the yellowjackets might have made. On the other hand, bleach smell in the house might help you determine where they might have migrated.
Glad you're resolving the issue, though. It's been a learning experience for me if these nasties ever get into my house again.
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