On Friday late afternoon, Lisa & picked out 5 colour-ringed Mediterranean Gulls amongst the pre-roost gathering at the Gann (some 25 Meds present) - one from Serbia (seen before), 2 from Germany (1 new, 1 seen before) and 2 white ones (one we couldn't read 1 digit, the other we got - 372A).
Well, 372A has some history! It was ringed in Belgium in June 2005 as a 3CY (i.e. it was a chick in 2003) with the colour ring 3E71. It has developed a pattern of breeding (I presume) in Belgium, and after that heading to West Wales - being seen in Ceredigion in 8 of the intervening years (most recently at Llanon last October), and in Pembrokeshire in 11 of them, including the most recent sighting here on 22/1/2021. The colour-ring was replaced on 14/5/2017 and 3E71 became 372A.
In terms of Pembrokeshire history, it has been seen in Fishguard Harbour (John Hayes, Richard Dobbins, Trevor Price & Adrian Rogers) and at the Nevern Estuary (Sam Baxter).
According to BTO bird facts, the oldest known Med Gull is 18 years 2 months. This bird would have hatched around June 2003, so by August, if it survives, could become a record breaker...looking at the past records, August in Ceredigion would be a very good bet. Photo below of the bird from Aberystwyth Harbour on 10/9/2018 from Ceredigion Birds blog (John A Davies).