Having seen the adult male RF Falcon extremely well last week, I decided to have a look at the 1st summer bird today. Arriving at 3:45pm, the bird was found to be ranging very widely and often very high up, due I suppose to the higher temperatures pushing insects higher up. It was never particularly close, but did occasionally appear low over the centre of the reservoir. At 4:10pm and again at about 4:30pm, the bird was high up and appeared a long way to the west - certainly beyond the line of poplars on the west bank, which takes it into Bucks. I would suggest if anyone has not seen it in Bucks yet, then tomorrow pm might be a good time to try as the hot temperatures might make it perform in a similar manner. When I left at 5:15pm, it was performing in more regular fashion fairly low over the southern bank.
Some interesting interactions with other birds: a Hobby dive bombed it at c:4:45pm, when it was fairly high up to the SW and was the first of 2 Hobbies seen to arrive, as the RFF had been a solitary falcon to this stage. A BH Gull pursued it over the southern reed bed at c5:00pm for a short while and the RFF seemed quite perturbed, taking evasive action with very swift flight.