Every year the pond is inhabited by a changing population of Hydrometra stagnorum [1]. Like the year before this year their numbers were small.
A small wasp I tried to photograph fell into the pond. Its struggle immediately drew the attention of two of the bugs which approached it cautiously.

I wanted to know what kind of wasp it was and therefore rescued it from its unlucky position. It turns out to be a male Proctotrupidae sp. [1], see here.

Literature
1 Nederlands Soortenregister