Herring or Black-blacked gull?

Herring or Black-blacked gull?

Observation - Herring or Black-blacked gull?. Description: The Skomer puffins were continually harrassed by gulls attempting to get them to drop their catches. I did not pay much attention to the gulls - and would like an identification of this gull if poss

The Skomer puffins were continually harrassed by gulls attempting to get them to drop their catches. I did not pay much attention to the gulls - and would like an identification of this gull if poss