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Update November 17 2004: added one crop of the November 6th Skua, plus comparison pics and amended commentary on separating it from Pomarine Jaeger.
Update November 15 2004: added extra pics of the November 6th Skua, plus commentary on separating it from Pomarine Jaeger.

This (what age?) South Polar Skua Stercorcarius maccormicki was seen on the November 06, 2004 pelagic out of South Padre Island, Cameron County; all images except the bottom one are with permission of Chris Merkord:

First for comparison here's the S.P. Skua seen on the October 1st Pelagic:

Here's the November 06 bird:-
Although there are many similaries between it and the October bird, note the primary molt progression on the left (from below) wing:- The October 1st bird has P1-5 new and full, P6 growing, P7 missing, and P8-10 old and very worn; the November 6th bird has P1-3 still growing-in, P4 missing, and P5 -10 old, but not as worn as the October bird. I feel that the November bird has dropped its central retrices, hence the lack of a central "bump"; it also has replaced all the secondaries, in contrast to the October bird:

This bird was clearly on the slim side for a skua, and reminded me of some of the rather dainty (presumed male - I've learned that, as in Raptors, the females are larger than the males) SP Skuas I've seen in Antarctica - which had a quite different jizz from the burly females. I noted in the field and on my poor photos of the Nov 6th bird that - once it had passed over and was flying away - it looked very Pomarine-like. I feel that the following features confirm it as a skua (and the plumage/structure make it a South Polar):

- The bill is long but deep, with a bulging gonydal angle and a large hooked tip that extends below the line of the lower mandible (in the field the bill looked uniformly darkish - note that first-cycle SPSKs have a paler bill base.) Pom does not have a bulging gonydal angle or a such a large hook. Nov 17th: WRONG! my very own pics of Poms on the same day show that they can have bills that look every bit as hooked as this bird. I do feel that there remains a subtle difference in the bill shape. I do notice that in comparison to the Poms on this page, this bird has a longer head/neck in flight profile - something I see in many skua photos.

- The underwing coverts are uniformly dark. From the evidence of many images of the jaegers, this could only occur in a Pom that was at least a 3CY, and I don't belive that a 3CY+ Pom could have body and head plumage like this bird - it would show a cap and paler belly (or if a true older dark morph, would be darker all over.)
I'd appreciate feedback on these ID elements (especially if the are in error!):

Note above/below that the inner secondaries may not be fully-grown (the very innermost do not protrude beyond the great secondary coverts), contributing to the narrow look of the wing base:

below note the humped, slightly paler back:

For some reason this angle of the photo seems to diminish the white bases to the old primaries; certainly they look IN THIS PHOTO much more Pom-like than skua-like, but keep in mind that these feathers are old and worn:

in the field the extent of white at the bases of the old upper primaries looked in range of a poorly-marked skua:

Nov 17: note in the crop below that with the primaries held rather bunched-up, the outer web of each P is obscuring the inner web of the next outermost P - except for P6 because P5 is missing - and there on P6 is the white inner web patch diagnostic of skuas:

Here are some pics of SPSK from publications I have - If you are the Photographer/Publisher/Author and want me to remove/amend your entry here, please contact me and I will do so immediately, with my apologies.

Note in the photo below the lack of the Primary white basal patch - this is because the outer web of each primary is dark, and with the wing almost-closed these outer webs cover the white patch on the base of inner web of the next-outermost primary:

In the photo below P9 may actually be missing, revealing the white patch on the inner web of P10:

In the pic below, note thew slight capped effect, somewhat limited white primary panel, and the pattern of the middle and lowermost flanks (pale/dark vertical blotches, as shown on the Nov 6 TX bird):

note below the tail held tightly closed, with a feather growing part-way up the underside of the tail - patterned exactly like that of the Nov 6th TX bird: