Hi all --

Barry and I looked at the photo of the possible B-H Gull as well and reached
the same conclusion as Clive -- from what can be seen (the photo is blurry)
we think it is a Bonaparte's Gull well into summer plumage, thus the red
legs. It does not appear large enough relative to the Ring-bills, the mantle
looks the same color as the Bonies' (it should be an obviously paler gray in
this light), the bill should show some red and the hood should be browner -
it looks quite black in the photo. Barry had seen a B-H Gull at Back River
the day before, perched with Bonies, and it stood noticeably taller and
longer -- a somewhat longer-legged appearance, obvious red base to the bill
(it was a first-winter bird), and pale gray mantle (with considerable brown
on coverts and primaries).

However we wanted to check and so drove up to Centennial Lake in early
afternoon, to find -- nothing. Well, nothing except a 40-knot wind, tons of
swallows and some nuts fishing (!).

Gail Mackiernan and Barry Cooper
Colesville, MD

on 04/03/2005 6:27 PM, Clive Harris at  wrote:

> Mike et al
> 
> I'm not sure that this bird is a good candidate for Black-headed. Bonaparte's
> can have quite bright legs when in full breeding plumage, consistent with the
> color that can be made out (and Black-headed can have quite dark legs, and
> bill, early in the breeding season).  The shape of the hood depends very much
> on how the bird is holding its head and is best used as a field mark if you
> can see the bird in the field in a variety of poses.  Also it does not
> actually look all that much larger to me than some of the obvious Bonaparte's
> - possibly it looks taller because its standing on something? I would've
> expected a Black-headed to look like the distinctly larger bird it is, more
> intermediate between the Bonies and the Ring-billed than this bird appears.
> Finally, the mantle looks as dark as any of the other birds, and a little
> darker than some of the Ring-billed, whereas you might expect Black-headed to
> be a little lighter than Bonaparte's when seen in overcast conditions.  Still,
> definitely worth checking again for more definitive views.
> 
> Regards
> 
> Clive Harris
> Cabin John, MD
>