Your sightings reported to Noah Perlut made it through the gull biologist community. Here are some details about the marked ring-billed gulls spotted in Portland. I was able to determine the codes from the numbers seen on the steel bands. One has a broken band, which is sometimes occurs after few years. These were banded in a 45,000 pairs colony just east of Montreal, Quebec.
Thanks for reporting these sightings and do not hesitate to submit other directly to me or through our web site http://gull.uqam.ca
Jean-François Giroux
Directeur, Département des sciences biologiques,
Université du Québec à Montréal (UQAM),
141 Président-Kennedy, SB-R880
CP 8888, Succursale Centre-ville,
Montréal, Québec, Canada H3C 3P8