Recent sightings of Pink-footed Geese on Long Island - New or returning?

Waterfowl can sometimes be tracked by noting differences in the patterning on their bills. This was pioneered by Sir Peter Scott and the Wildfowl Trust in the UK in the study of wintering Bewick's (Tundra) and Whopper Swans. I wondered if this same technique could be applied to gray geese, so began looking at the bill patterns of the recent spate of sightings from Long Island and New England. Click on the image for a slightly bigger version. I think we can say that the Pink-footed Goose at Sunken Meadow State Park, Suffolk, is almost certainly a different individual from the bird that spent several weeks in and around Kissena Park in Flushing, Queens during the winter of 2008/09. Whether it can be distinguished from the bird that wintered around Stony Brook (2007/08 and only a few miles east of Sunken Meadow) is harder to discern but needs more study. Likewise, the Montauk bird (2007/08, more than 40 miles further east and coincident with the Stony Brook bird) is fairly similar. I have been images of that bird but will need to dig them out. My thanks to Paul Gildersleeve and Ed Coyle for use of their images.