With this evenings dinner party rapidly approaching there was little time for gallivanting, with the first part of the morning given over to peeling and the second collecting a few last minute items. The day had started off rather dull but with frequent patches of sunshine not at all a bad day, I was lucky to catch one of the more prolonged spells of the warm stuff.
(Dark Phase) Long-tailed Skua - The Story So Far
It's coming up 3 months since I was on St Paul one of the 2 Pribilof Islands in the Bearing Sea, off the coast of Alaska. Being skillfully guided by Forrest Rowland, then working for St Paul's Tours,
From Forrest Rowland
To Paul Guris
- Date: Thu, 29 Sep 2011 13:49:24 -0600
- Subject: Re: Forrest's Dark Jaeger (Summarized Info)
All,
I've CC'ed Bagsy on this. He was the client with me who also observed the bird, took some photos and kicked up quite a conversation on his side of the "pond" as well! He'll be interested to read some of the commentary running through the mill. Fun stuff!!!
Best,
Forrest
On Thu, Sep 29, 2011 at 1:44 PM, Paul Guris <paulagics.com@gmail.com> wrote:
Gang:
We've been having a side conversation on this so I decided to summarize everything in one place. I also added Louis Bevier (since he's been in on the side chat), Todd McGrath,and Mary Gustafson.
Forrest's photos that kicked this all off:
Surfbirds discussion of the exact same bird photographed independently Jan. 14 (5 days after Forrest):
http://surfbirds.com/forum/showthread.php?t=9252
The blog post by the original Jan. 14 photography mentioned in Surfbirds:
http://bagsy-thecaptainslog.blogspot.com/2011/07/day-four-on-st-paul-pribilof-islands.html
Comment in Surbirds thread by Alex Lees:from Kjellen (1997)
No dark-phase bird was recorded among the 600 Long-tailed Skuas observed during the expedition*. Apparently, only two dark birds have ever been described. Both originated from western Greenland and are now in the collection at the Zoological Museum in Copenhagen. According to Boertmann (1994). both showed subadult characters, although the central tail feathers were fully grown. It is doubtful if these two skins really merit the claim of a dark phase in adult Long-tailed Skua but dark birds are not uncommon among juveniles (Cramp & Simmons 1983, N. Kjellen. pers. obs.).
*from the Kola Peninsula in the west to Wrangel Island in the east __________________
Dept. of Zoology, MCT/Museu Paraense Emílio Goeldi, Brazil.
Dutch Birds article linked to by Brian S in Surfbirds thread which claims the Greenland birds are adults:
http://www.dutchbirding.nl/content/j...pdf/2000-5.pdf
And a follow-up from Louis:I have Boertmann (1994) right here:pg. 35, right column, under "Remarks" for longicaudus: "A dark morph seems to be very rare (e.g. Furness 1987). Recent reports from Greenland have been non-breeders (Kampp 1982; Dändliker 1988). The two dark morph skins in ZMUC (both from West Greenland) both show some immature plumage characters, although both have fully elongated tail streamers."I can download the Kjellen paper from the Ibis later and send that to anyone who wants.I think this is fascinating that you have a bird that fits these earlier descriptions. The barring may not be indicative of age in this case. It would be good, though maybe impossible now, to get as much on the bird as possible. Bill morphology would help, but maybe you need a bigger oar!
That should be enough to digest for now.
-PAG
Paul A. Guris
See Life Paulagics
PO Box 161
Green Lane, PA 18054
215-234-6805
paulagics.com@gmail.com
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