Vega Gull and Slaty-backed Gull
2001 Sakawagawa-river Odawara Kanagawa Japan
(left), Slaty-backed Gull (right),
shows browner, more uniform tint. Vega Gull looks slimmer.
of Vega Gull look more contrasty compared with Slaty-backed Gull. But its
belly and flank are uniform brown unlike mongolicus .
Vega Gull (left), Slaty-backed Gull (right)
Gull (left), Vega Gull (right)