This adult-basic Mew Gull Larus canus brachyrhynchus?? was photographed by Alan Wormington at Wheatley Harbour, near Point Pelee, Ontario on March 31, 2006. Alan is wondering how such a bird differs from Kamchatka Gull (l.c.kamtchatkensis) - or if perhaps it may be that taxon?
Note the following features:-
- the overall size and bulk comapared to Ring-billed Gull (although there is a bit of Size Illusion at play in the first image, Alan assures me that in life the bird was as big as - or bigger than - most Ring-bills)..
- the darkness of the upperparts compared to Ring-billed Gull.
- the bill is about as thick as the RBGU at the gonys.
- on the folded outer primaries, the depth of black beyond the primary coverts is very thick (too thick for adult brach?).
In image below I've copied the Mew bill to above the RBGU bill, for direct comparison: