Gull x Glaucous-winged Gull
March 1st 2007 Choshi Chiba
Slaty-backed Gull x
Glaucous-winged Gull is probably not as common as Western
Gull x Glaucous-winged Gull in the west coast of North
America. But this type of hybrid is often hard to be noticed
among crowded flocks and its state is poorly known.
This individuals looked like a
pale Slaty-backed Gull at first glance. But its primaries
included grayish tone, and it looked as if it were a odd
Glaucous-winged Gull in some other situations.
The dark underwing bar is
indistinct than in pure Slaty-backed Gull.