A female Ectemnius cavifrons has found a place to stay for the night.
A few days earlier a female provisioned her nest with flies a little further away on that same nest block, block 4 on section II, possibly the same specimen.
Ectemnius female do not use the drill holes directly, instead they excavate deeper into the wood using the drill hole as a main corridor which is not closed of. The wood dust collected during the excavation is pushed behind her into the main corridor and out of the nest. From the outside the nest entrance is completely blocked with wood dust that periodically moves outward with a jerk. Below the entrance a large pile of it is built up.
Literature
1 Nederlands Soortenregister