This Lesser Black-backed Gull (Larus
fuscus ssp? ) was video-ed (upper three images,
by John and Barbara Ribble) and photographed (remaining images
by Martin Reid) at Victoria Landfill, Texas on February 7, 2000.
This bird was seen on one of those days when the degree of contrast
between mantle tones was very hard to see (and capture on film);
e.g. the difference between Laughing Gull (LAGU) and Ring-billed
Gull appeared very slight - thus the perceived tone of the mantle
is lighter than it may have been in real life. In direct comparison
with LAGU at the same angle it was very slightly darker. Note
the very rounded (Greater Scaup-like) head, and rather gentle
bill with a minimal gonydal angle. The most interesting feature
was the state of the primaries (more text below):
- note that during this viewing period P10 on the nearest wing
was dislodged and wedged just below the tip of P6, obscuring the
remainder of the tips. Note the small whitish crescent far from
the tip of P10 on both wings. Note in particular that P6 ( and
P4, P5 were similar) appears visibly blacker than P10 or indeed
P7 - P10 (mainly seen on far wing). P4 and P5 had large clean
pristine white apical spots (smaller on P5 than P4) and P6 had
a small white apical fringe, while P7 - 10 lacked any apical spots,
and while they looked somewhat worn there was no sign of the typical
indentation evident when the apical spot has worn away:
- Note the size compared to HEGUs (rather large - as big as small
HEGUs) rather tall stance (the legs looked a bit longer than typical
for graellsii, and were grayish-flesh, with no yellowish
tones), and the uniform, adult-like appearance of the back, mantle,
and wing coverts on the stationary bird.
- note the prominent black on P4; This pattern is very unusual
in graellsii (but normal in heuglini).
- The small amount of black in the tail and in the primary coverts
confirm that this is not an adult. Okay, so what is going on in
the primaries? At first glance it looked like it was undergoing
inner primary molt, but close inspection of the images leaves
me feeling that there is some kind of strange wear taking place;
it is odd that the gap is symmetrical at P6/P7, yet asymmetric
on the left wing at P4/P5. I lack the very latest Scando-European
articles about the identification of heuglini, but I understand
that its molt strategy is more similar to fuscus than graellsii/intermedius
in that it regularly starts to remolt the inner primaries in late
Winter/early Spring (can anyone confirm this and provide a reference?)
- in fact I would suggest that this is one simple feature that
all gullers should look for in Feb - April when checking LBBG-types.
Interestingly, One of the heuglini I saw in Bahrain in
early March showed a similar effect in the wing - look
at it here.
- in this last image, the gonydal angle looks more pronounced
.
I would appreciate getting any feedback
about this most interesting bird - thank you.
