We had a dinner disaster last night, when the old stove’s exhaust vent suddenly rained a flood of debris down into the skillet of beans and asparagus. Dinner went to the compost, and I remained grumpy for a while. But today I took the cover off the vent and banged the pipe to try to completely clear it. A lot of what emerged was mud wasp nests.

Mud daubers fill their nests with spiders to feed their larvae. Unlike some wasp species that fill a nest cell with one or two large spiders, mud daubers pack up to two dozen smaller spiders into each cell.

To capture a spider, the wasp grabs it and delivers a sting. The venom from the sting doesn’t kill the spider, but it paralyzes and preserves it, allowing it to be transported and stored in the nest cell for later consumption by the larvae. The mud dauber typically lays its egg on the prey before sealing the nest cell with a mud cap. Afterward, the wasp moves on to construct another cell or nest. The young larvae survive the winter inside the nest.

I’ve now sealed up the vent with foil (the exhaust fan is non-operational) so hopefully there’ll be no more dinner mishaps from that direction.