Thanks to comments posted by Kurt and Terry, I actually decided to actually
LOOK at my photos of the bird seen last week that many of us had been calling a
juvenile Pomarine Jaeger.Comparing some frame-filling photos taken in good
light, to illustrations/text in Birds of Europe and Sibley, this bird indeed
seems to be a juvenile Parasitic.The slender bill and the pointed central tail
feathers seemed to point to Parasitic but I wanted an expert opinion.
Here is the gallery of photos:
http://gallery.me.com/sparkystensaas#100743&bgcolor=black&view=mosaic&sel=0
I forwarded the photos to Klaus Malling Olsen, author of Skuas and Jaegers of
the World and here are his comments:
Hi SparkyThis is indeed Parasitic. The head is small and combined with slender
bille looking triangular varsus the heavier rounded with Ring-billed Gull bill
of Pomarine.
The size is perfect, Pomarines would look about equal in size to the gull, and
the shape as well with rather smart proportions such as slender body and rather
narrow arm.
Pom is more powerful with fuller body, in which centre of gravity often lies at
hindbelly,and broader base of the arm.
Central pairs of tail feathers often are slightly rounded in juvenile
Parasitic, not the sharper-pointed of older birds. However, they are way too
narrow to fit Pom.
Concerning plumage pattern, the bird shows a rather well-defined dark cap, in
Pom the head in juveniles invariably looks more uniform, lacking tendency to
pale hindneck bar.
Also, the rump only shows inconspicious pale pattering, not the distinctly
barred of Pomarine, where pale rump often looks similar patterned to American
Herring Gull. Hope my answer clarifies something!best wishesKlausI'm not
denying that some folks may have seen a Pom earlier, but all the photos I've
seen seem to be of this same bird. I've been on WI Pt for six straight days
watching the action and identifying this juvenile bird as a Pom...But a bird
flying at 40mph 100 to 200 yards out on Lake Superior is not an easy ID. The
detailed photos taken recently by several photographers have aided in the
positive ID. It is a lesson learned for myself. Either way, it has been a blast
watching these birds "perform."
I am also including Terry's friend's opinion here as well.
...sent the pictures to a friend in California, Stanley Walens, that
specializes in Seabirds - and sees thousands of Pomerain and Parasitic Jaeger
on the west coast while leading seabird trips.Here is what he had to say:well
you should be completely certain of the long-tailedthat's a loooong tailplus
look at the black trailing edge to the wing and the contrast between flight
feathers and covertsthe other one is a parasiticsize as big if not bigger than
ring-billed gulldark cap that does not extend onto chinbill long [too long for
long-tailed]warm reddish tone of upper sideunicolored upper wing [primary
coverts are darker but otherwise the wing's pretty uniform]white at the base of
the primaries on the upperwingpretty extensive white at the base of the
primaries on the underwingmore than 2-4 primaries with white shaftslack of
barring on uppertail covertsrestricted pale edges on the back and upperwing
coverts; not patterned enough for long-tailed pale breast mottled, not barred,
pattern to breast and bellypointed central rectrices [most noticeable in the
shot of the birds's underside] {the two central rectrices on a long-tailed are
rounded, and barely extend beyond the other tail feathers] {{this last feature,
plus the cap not extending below the base of the bill, eliminate pomarine}}
Sparky Stensaas
2515 Garthus Road
Wrenshall, MN 55797
218.341.3350 cell
[email protected]
www.SparkyPhotos.comwww.ThePhotoNaturalist.comwww.Birdnation.org
www.StoneRidgePress.com
www.KollathStensaas.com
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