Alicia Plotkin kindly forwarded this information about separating Glossy & 
White-faced Ibis. The first step is figuring out what age the bird is, so I’m 
looking for evidence about the Armitage Rd bird. 
- - Dave Nutter

> Begin forwarded message:
> 
>> From: Alicia <t...@fltg.net>
>> Date: November 5, 2017 at 10:17:47 PM EST
>> To: Ann Mitchell <annmitchel...@gmail.com>
>> Subject: Fwd: Re: [LABIRD-L] Identification and Status of White-faced and 
>> Glossy ibises in southeastern LA
>> 
>> Saw your post on the ibis ID and thought you might be interested in this 
>> discussion that took place recently on the Louisiana bird list, where the 
>> ranges of the two ibises overlap.
>> 
>> 
>> -------- Forwarded Message --------
>> Subject:     Re: [LABIRD-L] Identification and Status of White-faced and 
>> Glossy ibises in southeastern LA
>> Date:        Sat, 21 Oct 2017 14:03:21 -0500
>> From:        Steven W. Cardiff <scar...@gmail.com>
>> Reply-To:    Steven W. Cardiff <scar...@gmail.com>
>> To:  labir...@listserv.lsu.edu
>> 
>> Labirders-
>>      The only thing I would add is that adults in non-breeding plumage
>> retain the "reddish/chestnut" upper wing coverts (shoulder).  This is how
>> they can be distinguished from immatures.  So, if you are panning through a
>> flock during fall-winter, individuals with the chestnut upper wing patch
>> will be adults and should have their definitive iris and facial skin colors.
>> 
>> Steve Cardiff
>> 
>> On Sat, Oct 21, 2017 at 11:52 AM, James V Remsen <naja...@lsu.edu> wrote:
>> 
>> > LABIRD:  Part 2:
>> >
>> > Here are the ID problems, as I understand them so far. Steve, Donna, and
>> > others please chime in to repair any damage below:
>> >
>> > ==========
>> >
>> > JUVS: these are the brownish necked individuals with few if any streaks,
>> > often with pale blotches on the bill.  These are NOT identifiable to
>> > species as far as anyone knows and should always be reported as Plegadis
>> > sp. in SE LA (including Florida and River parishes). All of them have gray
>> > facial skins and dark eyes.
>> >
>> > ==========
>> >
>> >  IMMS: In first basic plumage, the neck becomes streaked.  The facial skin
>> > is gray in both species.  The iris in White-faced at some point becomes
>> > red.  So, if you do see a streak-necked bird with a red eye, then it is
>> > WFIB, but a dark-eyed bird cannot be safely identified.  A real problem is
>> > that as White-faced matures, it can pass through a stage that looks very
>> > Glossy-like in still having dark eye and facial skin but having traces of
>> > white around face that can make it look like a Glossy.  For example, the
>> > following photos were found by Tony Leukering from CA and NV, where GLIB
>> > would be extremely unusual, so these are presumably WFIB:
>> >
>> >  California:  https://macaulaylibrary.org/asset/70670231#_ga=2.29961980.
>> > 25890241.1507509707-334541348.1399337695
>> >  California:  https://macaulaylibrary.org/asset/68874791#_ga=2.
>> > 265350860.25890241.1507509707-334541348.1399337695
>> >  California:  https://macaulaylibrary.org/asset/34774341#_ga=2.59837166.
>> > 25890241.1507509707-334541348.1399337695
>> >  Nevada:  https://macaulaylibrary.org/asset/69398871#_ga=2.
>> > 265350860.25890241.1507509707-334541348.1399337695
>> >
>> >
>> > An open question is how early WFIB begin to acquire a red iris.  We can
>> > all contribute to this by uploading photos to eBird.
>> >
>> > ==========
>> >
>> >
>> > ADULTS in basic (non-breeding) plumage, i.e. streaked neck, lack of
>> > breeding colors around face (but wing coverts still glossy green etc:  the
>> > most reliable way to tell them apart is by iris color: red in WFIB, brown
>> > in GLIB.  The facial skin should also be pinkish in WFIB, gray in GLIB.
>> >
>> >  =============
>> >
>> > Summary:  FIRST, put your bird into an age category and then ….
>> >
>> >
>> > 1.    JUVS: cannot be identified to species and should always be listed as
>> > Plegadis sp. In SE LA.
>> > 2.    IMMS: IF the iris is red, then it’s WFIB; otherwise, should always
>> > be listed as Plegadis sp. In SE LA.
>> > 3.    ADS (non-breeding): If you can see iris color or facial skin, then
>> > you can ID them; otherwise, should always be listed as Plegadis sp. In SE
>> > LA.
>> >
>> >  I am skipping the topics of first alternate plumage and hybrids (which
>> > are not infrequent), but beware of birds with mixed or intermediate
>> > characters.
>> >
>> > I am going to hit the “reset button” for SELA Pleads, so all you eBirders
>> > should brace yourselves for a barrage of messages.
>> >
>> > ===================
>> >
>> > Dr. J. V. Remsen
>> > Prof. of Natural Science and Curator of Birds
>> > Museum of Natural Science/Dept. Biological Sciences
>> > LSU, Baton Rouge, LA 70803
>> > najames<at>LSU.edu
>> >
>> > > On Oct 15, 2017, at 2:17 PM, James V Remsen <naja...@lsu.edu> wrote:
>> > >
>> > > LABIRD:  It is clear from eBird data that observers are over-reporting
>> > Glossy Ibis in southeastern LA based on (1) assumption that most or all
>> > Plegadis there are Glossy, and (2) treating any Plegadis as Glossy unless
>> > it has obvious white facial markings or red iris.  I have made these
>> > mistakes myself.  Both assumptions are wrong.
>> > >
>> > > To force us all to pay closer attention to their status and
>> > distribution, I have zeroed the eBird filters for both species for all of
>> > southeastern LA as far west as Terrebonne and around L. Pontchartrain
>> > despite the facts that both species are expected there.  Briefly, the only
>> > way to ID non-breeding plumage Plegadis is by iris color (red in WHFIB,
>> > dark in GLIB), and many WFIB to not attain their red eyes until late in
>> > their first year, so dark iris is not sufficient to call a bird a Glossy.
>> > More later in a subsequent message on what I understand concerning their 
>> > ID.
>> > >
>> > > So, henceforth, you will have to defend your species IDs on these two in
>> > the above regions.  Otherwise, just enter as Glossy/White-faced.
>> > >
>> > >
>> > >
>> > >
>> > > ===================
>> > >
>> > > Dr. J. V. Remsen
>> > > Prof. of Natural Science and Curator of Birds
>> > > Museum of Natural Science/Dept. Biological Sciences
>> > > LSU, Baton Rouge, LA 70803
>> > > najames<at>LSU.edu
>> > >
>> >
>> >
>> 

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