Mew Gull — Blue Marsh Lake, Berks County; January 3, 1992. Photos by Frank Haas. This bird was originally found on January 2nd by Jonathan Heller at nearby Lake Ontelaunee. Note the unmarked, yellow bill, the dark eye, the dark smudges on the head and neck, and the slightly smaller size and darker mantle compared to the surrounding Ring-billed Gulls green new balance. This bird represents the 1st record for Berks County and the 1st record for Pennsylvania!
This photo shows the wingtip pattern, revealing the large amount of white on the outermost primaries.