Was it depositing eggs?

It was hot overnight, and the dog wanted to be on a bed. I didn’t notice S discouraging her. Mid morningish, the lads and I went down the path to Fidelis beach for a swim. When I was drying myself I noticed a flying insect land on a silvered log, looking to me as if it was finding places to leave eggs. 

Maybe not, as when I looked up the book we have on insects and spiders, the only one that looks like this is a solitary wasp. The black cockroach hunter is widespread in New Zealand, and specialises in catching and eating the native cockroach.

Back to the city this evening to finish moving out of the apartment.