In March 2010 Pam Birley captured this gull with the remote camera. She wrote "I saw a California gull recently and attach pics. You don't seem to have any in the taxonomy pages. It's not a rare gull but this maybe the first I have seen at RR." Indeed it is one of those gulls which has fallen through the cracks so this is a rather late addition to our taxonomy.
Preening
This adult plumage is reached after 4 years. Note the black tip on the bill and the yellow legs which distinguish it from the Western Gull