From photos as the Caspian Tern flew off over the road I managed one photo where the lettering could just about be read. I thought it was HDX. This was sent off to the Swedish Ringing scheme. there reply suggested the bird must be HOK, presumably the only viable match.
Details below:-
Caspian Tern Sterna caspia
Stockholm
Sex/status:
Age: Nestling wing: 115 mm weight: 380 g
Date: 2017-06-20
Place: SWEDEN, SÖDERMANLAND, OXELÖSUND, LÅNGA HÅLLET
Coordinates: 58º 36´N 16º 59´E
Other marks: Colour ring H0K RED/WHITE
1st ringing recovery of this bird since it was ringed
Details below:-
Caspian Tern Sterna caspia
Stockholm
Sex/status:
Age: Nestling wing: 115 mm weight: 380 g
Date: 2017-06-20
Place: SWEDEN, SÖDERMANLAND, OXELÖSUND, LÅNGA HÅLLET
Coordinates: 58º 36´N 16º 59´E
Other marks: Colour ring H0K RED/WHITE
1st ringing recovery of this bird since it was ringed


