Hi Starfish
Thanks for the information. I was a little skeptical but I spoke to John Allcock. He amplified your recording and confirmed that it is an Arctic Warbler.
The 2014 Bird Report gives the extreme dates for Arctic Warbler as 18 August to 4 December. However, as John pointed out, the Avifauna does mention a record of Arctic Warbler at Victoria Barracks on 24-25 December 1987.
Whatever, your sighting is the first ever for January and the fact that it is a long-staying bird is of great interest.
Shows what a regularly-watched local patch can turn up!!
David
