This Common Buzzard flew over the lake as I watched the Tern. It was shrieking quite a lot and it was occasionally mobbed by Carrion Crows.
There was a pair of Great Crested Grebes nesting under the overhanging vegetation on the far side of the lake. Here's one of them doing a bit of nest strengthening.
The Tern was catching fish and taking it back to the floating raft where it obviously had bred this year. When I looked closer at might my photographs I could see that there were two young, but only one adult bird was present. Perhaps it had been predated. And then, as I was leaving I noticed something in the water near where the Tern was perched on the floating raft. Is is just a fish, or perhaps worse, a mink? I can't quite make it out.