A look in the garden pond reveals far fewer tadpoles than a week ago. Hopefully meaning there are plenty of hungry carnivores also in the pond.
I have found identifying this Diving Beetle difficult, the only one I've really known before is the big black chap (Dytiscus), and only then because it tried landing on the bonnet of the car. Apparently they do this as the reflection looks like water. The one above I believe to be Acilius, and a male due to it's smooth wing cases, unless someone can tell me different.