During my lunchtime gull count, I came upon a 1st winter gull that I
couldn't place.  First reaction was a very small Great Black-backed Gull,
but the field marks (small size, lighter back, head shape) didn't add up.
I got Jim Stasz, who had his camera with him and got great pictures of it.

He got some great pictures of the gull at rest and with wings extended,
which may confirm this (possible Slaty-backed Gull).  When the wing was
extended, Jim photographed the primaries and we noted the dar outer webs
of the primaries.

Also present was a first year Iceland Gull.  The birds flushed at the
passing of a hawk, but most resettled.  I am not sure if the mystery gull
is one of them as I had to get inside.  I will check again later today.

The gull seemed to be smaller then the Herring Gulls nearby, which is what
I first noticed about the bird.  It didn't contrast in size with the
Ringers as much as I would expect from a Great Black-backed.  Jim will be
placing his photos on the web for others to look at.  Mantle also was much
lighter then expected from a Great Black-backed Gull.  Structure was all
wrong for a Lesser Black-backed Gull.  Bill is all black.  I'll post again
if I relocate the gull....

Fred Shaffer
Patuxent MOS