No interactions present.
Fooled me for a minute, but I think you're right. Not the usual red bill but black; right size though. White patch above bill.
I'll not be caught out so easily next time (or perhaps I will ;-))
Terns can be quite tricky but I confident this one is common
...usually see only common terns, with the odd black tern thrown in. anything else is unusual. I like they way they're so elegant in the air, but look so daft on the ground, with those silly little legs and feet. Smashing birds.
Mostly Sandwich Terns here (all year) with Common and Artic (and the odd Little and Roseate) spring and autumn
Lat/Lng: 50.7179, -1.8434
OS grid ref: SZ111909