I heard back from the BTO and it turns out that this bird was ringed in Glen Esk in Angus by a member of the Tay Ringing Group on 31 May 2011.
|Red - Glen Esk, Angus|
Blue - Castlewellan Lake, Co. Down
It's strange, as I was back in Scotland last weekend and spent a couple of hours with Ben looking for colour-ringed gulls in Arbroath and, for some reason, I was telling him about this exact bird!
According to the ringing report I received, this is a movement of 354km SW and the time between ringing and re-sighting was 595 days.