As I left the front of our house in Rigby Street, A-in-M, intending to go the Wigan Flashes, this bird was callng persistently from the top of a mature Beech tree. It did so for approx 30 seconds, before I got a brief view in the canopy. It then flew strongly across Millingford Brook, probably in to a private part of the wood. Viewing of that area is possible from the public part of the wood, off Woodedge. There was lots of Goldcrest and tit flock activity around the point where Millingford and Down Brook join, plus a brief view of a warbler. No further sign by early afternoon, but it's unfortunately a real needle in a haystack job, lots of gardens in the vicinity with mature trees, as well the wood itself. I'll keep an ear open around the garden.