In the afternoon of the second day of 2017, a mid-coast Maine birder noticed a pair of Pink-footed Geese among a flock of Canada Geese feeding on a snow-free athletic field in Rockland, ME. Since this would be a life bird for me, I ventured to Rockland the following morning, where I quickly located the geese at the previously reported spot.
Pink-footed Geese nest in Greenland, Iceland, and Svalbard and migrate to parts of Europe to spend the winter, except when they don't. Increasingly, small numbers of Pink-footed Geese are seen in northeastern North America in fall and winter (see this eBird occurrence map). The Maine Bird Records Committee lists nine records for this species in the state, all within the last decade. This Rockland duo will be the tenth state record, and the first record for Knox County.
Given their smaller size, brown (instead of black-and-white) heads, and bubble-gum pink feet, spotting a Pink-footed Goose within a Canada Goose flock isn't too tough, assuming you can get close enough to the flock; although, they don't stick out as obviously as another goose with pink-feet, shown below.