Natural Selection

Preston Dock is a popular place for people to take in the views across the water whilst eating their fast food. Gulls with similar tastes loiter during the day, before their numbers are swelled by others coming in to roost or bathe pre-roost. Over the years many Black-headed Gulls have been caught by hand and ringed there, with some being entirely or largely resident and others leaving to breed elsewhere.

These birds are marked with blue darvic rings starting with a 2. I have recorded ‘local’ birds at the dock that have visited Poland and The Netherlands. The one below 2J27 went on to visit Sweden and I also saw it subsequently on the Wyre Estuary at Skippool this year.

Somehow it feels more satisfying to see the birds sporting foreign rings though. In the last few weeks three birds from Denmark have been on the jetties on different occasions, though never together. Pictures follow below.