Unidentified gull

Unidentified gull

Observation - Unidentified gull. Description: We are looking for help in identifying this gull. Any suggestions will be greatly appreciated. The coordinates given here are not where this bird was seen. We did not want to give the actual location because we would like to run a blind experiment. We

We are looking for help in identifying this gull. Any suggestions will be greatly appreciated.

The coordinates given here are not where this bird was seen. We did not want to give the actual location because we would like to run a blind experiment. We think this may have been a rare sighting and we do not want to bias anyone's identifications.