Ontario Field Ornithologists
Gulls, Terns, and Skimmers
Great Black-backed Gull
with Lesser Black-backed Gull below.
left, 1st Winter, right 2nd Winter.
attacking a Long-tailed Duck.
2nd alternate, eating a Mooneye.
juvenile, with 1st basic Glaucous Gull on right.
1st basic right with Glaucous Gull.
2nd year, with 2nd yr. Lesser Black-backed Gull on left.
collection of scientific data adhered to Bird Studies Canada's Project Nestwatch monitoring code of conduct.