I know its a bit small in frame, but they have a delightful jizz about them. Almost Black Tern-like.
Only the twelth record this century for the county, the last one was on Brogborough lake on 29th October 1989. Others were in 1988, '83 (2), '78, '70, and five (!) in 1952. You could say it's been quite a blocker for the new gen of Beds birders.
My shot are poor when you compare then to those of MST's boat shots - check them out here.
Well done to Pete Smith for this magnificent find - it was well worth the 50 year wait, eh, Pete!