Bill, I believe this same individual was in Larimer County in December. Here
is a photo I took at Lake Loveland on Dec 28:
http://www.pbase.com/quetzal/image/140599429. I did not see it on Jan 1.
When did you first start seeing it? I agree it is a confusing bird. I saw it
with its wings extended and it has very dark primaries like Lesser
Black-backed Gull (LBBG), not the pale inner primaries of Herring Gulls. The
wing-tips extend beyond the tail more than expected for Herring Gull, but
appropriate for LBBG. Note that in my photo, it is the same size as the
adult LBBG on its right. It is a bit smaller than the Herring Gull behind it
and to its left. I did not get a good look at the tail and rump. Dark rump
with all black tail would be a Herring Gull trait. Pale tail base, and pale
rump would be more like LBBG. First-winter LBBG should be extensively white
on head and underparts, but juvenile LBBG can be all brown like this bird,
according to textbooks. This bill seems thin enough to be LBBG, and yet it
is not quite as black as I would expect for LBBG. My thought is that this is
either a LBBG in juvenal plumage (i.e. its molt to first-basic plumage has
been delayed), or this is a LBBG with some Herring Gull genes from a past
hybridization event (progeny of a pure LBBG and a hybrid Herring x LBBG) or
an F1 (first-generation) hybrid LBBG x Herring Gull (progeny of a pure LBBG
and a pure Herring Gull). I am curious to read others' comments.
Nice photo and an interesting bird.
Nick Komar
Fort Collins CO
-----Original Message-----
From: kickback
Sent: Saturday, January 07, 2012 9:23 PM
To: Colorado Birds
Cc: bill_ko...@msn.com
Subject: [cobirds] Gull Id assistance (pics)
I have been looking at this gull for a while and I think it is a
juvenile/first cycle herring gull but it seems too dark and charcoal
colored.
http://avoapples.com/birds/_MG_9912_cr.jpg
http://avoapples.com/birds/_MG_9948_cr.jpg
Comments would be appreciated, especially comments explaining why it
is what it is. The gull was at Pueblo Lake.
Thanks
Bill Kosar
bill_ko...@msn.com
Colorado Springs
--
You received this message because you are subscribed to the Google Groups
"Colorado Birds" group.
To post to this group, send email to cobirds@googlegroups.com.
To unsubscribe from this group, send email to
cobirds+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/cobirds?hl=en.
--
You received this message because you are subscribed to the Google Groups "Colorado
Birds" group.
To post to this group, send email to cobirds@googlegroups.com.
To unsubscribe from this group, send email to
cobirds+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/cobirds?hl=en.
