Date: 12/27/18 9:35 pm
From: Leith McKenzie <dmarc-noreply...> (Redacted sender loinneilceol for DMARC)
Subject: [obol] Fw: [BIRDWG01] Intermediate Egret - Lane County Oregon
 Cross posting in case anyone has relevant photos.
At this point in the discussion, it seems to me that any and all "field marks" other than the size of the bird (and perhaps Mr Reid's ratio below) have been both expounded and called into question at length by experienced birders. (e.g. Intermediate does not have a kinked neck) . . .   Maitreya  

----- Forwarded Message -----
From: Martin Reid <upupa...>
To: <BIRDWG01...>
Sent: Thursday, December 27, 2018 5:37 AM
Subject: Re: [BIRDWG01] White Egret - Lane County Oregon

Group:
Are there any photos that provide a clear look at the tarsus and foot?  INEGs have big feet!  Well, toes actually.  With a good view this is often obvious - rather like the difference between the toes of Orange-breasted Falcon versus Bat Falcon.
Given that INEG has a proportionally shorter tarsus than GREG, a comparison of tarsus length to toe length might provide a useful difference.
I took the liberty of downloading the images at the following two web pages, and used them to create a ratio of tarsus length (from bend of knee to base of “exposed” toe) : toe length (base of “exposed” toe to tip of tail).  The measurements were made with each element of the leg in the horizontal position.
The results: Great Egret 1.67 : 1 ; Intermediate Egret 1.25 : 1

Even allowing for imprecise measurement and that this is a sample of one, this suggests that there is a significant difference in leg and foot structure between the two taxa.

https://blog.duncraft.com/wp-content/uploads/2009/10/File-Jun-14-12-13-41-PM-1080x720.jpeg <https://blog.duncraft.com/wp-content/uploads/2009/10/File-Jun-14-12-13-41-PM-1080x720.jpeg>
https://ebonph.files.wordpress.com/2012/02/intermediate-egret-neon.jpg <https://ebonph.files.wordpress.com/2012/02/intermediate-egret-neon.jpg>

Martin

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Martin Reid
San Antonio
<upupa...>
www.martinreid.com







 
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