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Lokalitet:
Petaluma, California - USA
2013-02-18
Fotograf: Richard Bonser - Se profil

Titel: juvenile Glaucous Gull x Glaucous-winged Gull

Uploadet 2013-02-24 Publiceret 2013-02-24 Larus-hybrid sp. Gull hybrid sp.
5 1614
Kommentarer
Jens Toftelund Madsen
25. feb. 2013 kl. 11:19
Hi Richard, Could you give some input to why this is a hybrid? If I saw this bird in Denmark I would mostlikely just have called it a Glaucous Gull. Best regards Jens
Richard Bonser
25. feb. 2013 kl. 19:05
Yeah structurally the head is all wrong for a Glauc - it's one dopey looking beast with that large eye, lacking any snouty look while the dark tip bleeds into the gape on close inspection as well as the thick set structure more akin to Glauc-winged. Additionally, even for a Glauc, it's very short-winged... Cheers Rich
Klaus Malling Olsen
25. feb. 2013 kl. 21:40
I don´t think the structure is "totally wrong" for a Glaucous, regarding that we have a West Coast bird here. The wing is short, but similar short wings can be seen in many males, which however normally will appear "bruter2 than this bird. But few characters are wrong for Glaucous: 1: the bill is too dark at basal parts, and the black tip has a diffuse division from the paler basal parts, whereas a 100% Glaucous should have pink bill with sharper divided black tip. 2: the presence of some more uniform grey feathers in breast-sides, flanks and hindneck is a character from Glaucous-winged. ID of the gull as a hybrid Glaucous x Glaucous-winged Gull is thus advocated.
Jan Jörgensen
25. feb. 2013 kl. 22:16
Good call of charaters by Klaus, which suggest the initial id. JanJ
Jens Toftelund Madsen
26. feb. 2013 kl. 11:52
Thanks Richard and Klaus for educating me (and others?) on this challenging hybrid type. Best regards Jens

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