Slaty-backed Gull / Western Gull?

Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull
Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull	Slaty-backed Gull / Western Gull
Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull
Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull	Slaty-backed Gull / Western Gull / American Herring Gull