This gull was photographed in Bahrain in early March 1999 by Martin
Reid. it was one of the most striking first-basic birds I saw
there, being very large indeed, and in having extensively dark
mantle/scaps plus almost all lesser and median coverts replaced
and the inner greaters also new:
in the image below it can be see towering over the many barabensis
nearby - but what about that adult bird next to it; size-wise
and structurally they are quite similar, but what IS this adult
bird? it has the size, dull legs and extensive white in the primaries
of a ponticus/cachinnans, yet the eye is clearly
pale (but check these apparent pale-eyed pont./cach. here and here)
and the head/bill shape looks odd for what would be a male cachinnans
(due to size):
In flight note: the underwing coverts and axillaries are strongly
barred; the inner primaries have the classic pattern of the ponticus/cachinnans/barabensis
group, as do the plain-centred, pale-edged remaining juv. greater
coverts; the striking pattern of the first-basic median and lesser
coverts (of which the outermost have not been replaced yet); the
broad tail band with fairly heavy barring on the central uppertail
coverts;
The molt of the wing coverts is strongly against this bird being
a ponticus/cachinnans; size and structure would
make this an extraordinary barabensis; the paleness of
the inner primaries plus the extensive dark centres to the scaps
look wrong for heuglini - and the distinctive pattern of
the median/lesser coverts looks wrong for any of the above - so
what might this be?
Update: after correspondence with
a few gullers, I feel that this is a heuglini, despite
the pale panel on the inner wing and large dark centers to many
scapulars. Further, I feel that the large adult bird next to it
is probably a BPH-type heuglini (explaining the large amount
of white in P10 from below) and that this young bird may also
be a BPH-type. As always, more
comments would be appreciated.
