[obol] FW: Is it an eagle or what?

Mon Dec 3 18:51:02 PST 2007

You can clearly see that the bird has a black bill and a yellow cere,  
which suggests a subadult Bald Eagle. …” Ferruginous hawks have a  
very apparent yellow bill…”

I suggest that you look more closely at Ferruginous Hawks at your  
next opportunity. They have a dark bill and a yellow cere and these  
characteristics hold true for all ages and all morphs. (Read the  
species traits in Wheeler's Raptors of Western North America or other  
authorities). As you say, they do have a large gape but it cannot be  
clearly distinguished in this photo as to size. In no plumage does a  
Bald Eagle have this much clear white underneath. Young birds are  
very mottled not solid white. Adults, or near-adults are the only  
Bald Eagles with white heads and when the head is all white, the body  
is black. You suggest that Bald Eagles have "shorter tails that do  
not protrude beyond their wing tips." However, the photo seems to  
show a tail slightly longer than the wing tips and what can be seen  
of that tail is white, which again suggests Ferruginous Hawk.

I am not saying that this is definitely a Ferruginous Hawk but that  
is my best guess based on what I can see. With the lighting  
conditions of this photo, it is hard to be sure of any ID with  
certainty. However, Ferruginous Hawk is consistent with everything I  
can see in this photo and many features are inconsistent with Bald  
Eagle.

As eagles mature their bill gradually grows out from the cere.

What do you mean by this? The cere is a dermal covering at the base  
of the bill that covers the nostrils of some birds (hawks, eagles,  
pigeons, some parrots). The bill does not grow out of the cere. The  
bill is well formed by the time the bird fledges. The rhamphotheca is  
the keratinized outer covering over the bone and makes what we see as  
the beak. The rhamphotheca grows throughout life in ALL birds. As  
birds eat and preen, the rhamphotheca is worn. This wear is replace  
by continual growth of the rhamphotheca. In some birds it, or  
portions of, are shed annually, as in puffins which have a very large  
rhamphotheca during the breeding season and a much smaller one in the  
winter. In Bald Eagles, the rhamphotheca and cere are both dark in  
juveniles.

Bald Eagles have very large beaks at all ages and the beak on this  
bird looks too small in proportion to the head to be that of an eagle.

An additional note about Golden Eagles: Their bill is NOT entirely  
yellow. To quote Wheeler: "The distal half of the bill is blackish  
and the basal half is pale blue." They do have a large yellow cere  
and fleshy gape.

OBOL has generally been a safe and respectful place on which to offer  
help to others. I would request that you don't completely disregard  
the suggestions of others so blatantly in the future. Also, please  
look carefully at your “facts” as some of the things you say here are  
simply untrue or incomplete.

Dan Gleason

-------------
Dan Gleason
dan-gleason at comcast.net
541 345-0450

On Dec 3, 2007, at 3:54 PM, Devon Batley wrote:

>
>
> From: devon_batley at hotmail.com
> To: kirkpat at charter.net
> Subject: RE: [obol] Is it an eagle or what?
> Date: Mon, 3 Dec 2007 23:54:15 +0000
>
>
> you can disregard both the suggestion of an Osprey or Ferruginous  
> hawk. Though your friends' photo is washed out. You can clearly see  
> that the bird has a black bill and a yellow cere, which suggests a  
> subadult Bald Eagle. As eagles mature their bill gradually grows  
> out from the cere. Conversely Golden Eagles have yellow bill from  
> the get go. Ferruginous hawks have a very apparent yellow bill &  
> cere w a large gape, visible from quite a distance. Also the head  
> shape is wrong. While Ferruginous are large hawks they have a bulky  
> chest which makes there head look small. The bird in this photo has  
> a large protruding head. It is clearly not an Osprey as it has no  
> eye stripe or brown necklace.
> Bald Eagles have large head and shorter tails that do not protrude  
> beyond their wing tips. If you are still unsure consult the Wheeler  
> Guide to Raptors of North America. This is the raptor  
> identification bible.
>
>
>
>
>
>
> From: kirkpat at charter.net
> To: yaakovm at comcast.net; obol at lists.oregonstate.edu
> Date: Mon, 3 Dec 2007 14:20:56 -0800
> Subject: Re: [obol] Is it an eagle or what?
>
> How about Osprey.
>
> Doug Kirkpatrick
>
> From: obol-bounces at lists.oregonstate.edu [mailto:obol- 
> bounces at lists.oregonstate.edu] On Behalf Of Jordan Epstein
> Sent: Monday, December 03, 2007 1:04 PM
> To: obol at lists.oregonstate.edu
> Subject: [obol] Is it an eagle or what?
>
> To All On OBOL:
>
> A friend recently (mid-November) took this photo hiking near his  
> house in Arnold, CA.  The photo was taken at Lake Alpine, which is  
> about 100 miles northeast of Stockton.  He asked me what the bird  
> was and I’m not sure.  It’s clearly a large raptor, probably an  
> eagle.  But I wanted to share it with you to see if there were  
> other possibilities.  The photo quality is not good so a clear  
> identification might be difficult.  Any help would be appreciated.   
> The photo can be found at http://share.shutterfly.com/action/ 
> welcome?sid=8BYs2rdq0bMKK.
>
> Jordan Epstein
>
> SW Portland
>
>
>
>
> Get closer to the jungle… I'm a Celebrity Get Me Out Of Here!
>
> The next generation of MSN Hotmail has arrived - Windows Live Hotmail
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