A Lesser Black-backed Gull seen in North Plymouth this fall has fostered speculation as to whether it was the same individusal as has been seen for several years at Jenny's Mill Pond on the southern part of town (certainly not a very long flight). Speculation has been that they are two different birds since apparently the Jenny's bird hasn't appeared to wander much over the years.
I got this shot of the Jenny's bird in January and it is helpful in comparing with the one I took today (11/20/12)(click previousin upper right to see it). Based on differences in the density of the dark markings near the eye and especially the markings on the bill, I think they are definitely two different birds.