Thanks for your reply, max, me now slightly wiser.
Was Turweston a wartime field? Would they have questioned it then? Is this "prior use"?
Shotgun, anyone? I like a nice horse steak.
[Edit: as an aside, the aerodrome I fly from has Lapwings...OK, I know they are birds...they sit in flocks in excess of 200 in number adjacent to aircraft landing and departing(within say 20 feet), and appear to be totally unconcerned, and do not interfere or pose a birdstrike threat. Perhaps it is because they have been naturally reared amongst aeroplanes]