I found this apparent 1st cycle California Gull (CAGU) at Niles Pond in Gloucester, Massachusetts (USA) on 3 March 2007. These digiscoped images from 3 separate photographers have been cropped and resized, but otherwise unaltered. Key field marks supporting identification of CAGU are: 1) intermediate size between Ring-billed and Herring Gulls, 2) all dark tail, 3) blackish-centered scapulars with broad dark-gray borders, 4) barring on vent, 5) slight darker contrast of greater coverts compared to median coverts, 6) bicolored bill, 7) pattern of white on head, and 8) (not shown in photos) long primary extension beyond tail (longer than Herring Gull, and perhaps a smidge shorter than expected for Lesser Black-backed Gull). In flight, the pale "window" in the inner primaries was less evident than that for typical Herring Gull.

The bird was seen between 12:10 and 12:40 pm by many observers. Unfortunately it flew westward (towards the State Fish Pier I suppose).

This is an exceedingly rare species in Massachusetts. Comments disputing or supporting its identity are welcome, or they can be emailed to me at quetzal65@comcast.net.

Comment added 17 April 2007: Based on input from others, I don't think that this bird can be definitively identified. The bill pattern and structure is not a strong match for CAGU. I believe that a hybrid American Herring Gull X Lesser Black-backed Gull could match this bird. - NK