Re: [SBB] around the bay (6/1)

[Chuq Von Rospach <[[email protected]]>]

On Jun 2, 2006, at 8:17 AM, Bill Bousman wrote:

> This looks like an immature Red-tailed to me.  It seems to be on  
> the lighter end of this variable species.  The tail and flight  
> feathers all show even bands, as is characteristic of most Red- 
> taileds.  There is a thin, somewhat dark patagium.  The belly  
> streaking looks about normal to me.  If it was really bigger than  
> the other hawks it might be female, but size can be really hard to  
> judge.
>
> I don't know why you suggest Ferruginous, which would be an  
> extraordinary find at this time of year.  "lack of banding on the  
> tail" does not fit with the photo you posted which shows clear  
> bands (as seen on juvenile Red-taileds).  Wing shape can be  
> valuable with experience, but is tricky.  To me, this shape appears  
> typical of Red-taileds.  For Ferruginous, the underwing pattern is  
> important, but I would not expect any banding, as is seen on this  
> bird.

Thanks, Bill. This is what I was hoping for. I realize it'd be  
extraordinary this time of year (sibley's shows us -- at best -- at  
the very edge of their territory). I'm trying to make my best guess,  
rather than just throw up my hands, since I learn better from the  
feedback that way. Appreciate your patience.

I confused with with my use of "banding" here. What I was trying to  
imply was the dark streak across the tail feathers, as you see on,  
say, a Cooper's, or if you look in Sibley's at the Gray or zone- 
tailed hawk where he uses the term. That limited my choices to (I  
felt) red-tail or ferruginous.

After that, the reason I guessed ferruginous was twofold. One was  
size, and perhaps I allowed myself to get surprised by that third Red- 
tail that showed up. Of the three, the bird pictured was by far the  
largest -- and I felt when I first saw it soaring that perhaps it was  
the golden eagle that's been seen at shoreline; that big. The second  
bird that seemed to be paired with it was a good 6" in wingspan  
smaller, but similarly marked; the third individual had a clearly  
visible red tail, and was noticeably smaller (4"? probably not  
another six) than the smaller of the two birds. Since the red tail  
indicates adult and the lack of one indicated a younger bird,  
combined with that much size difference, put red tail in doubt for me.

It's not very visible on that picture, but the bird had a clear  
darkening of the tip of the beak. Sibley's shows that on ferruginous,  
but not on red-tail. on the other hand, the eye color and the  
coloration of the feathers around the face (the "beard" and  
"sideburns") leaned more towards red-tailed. I finally decided to  
lean on bird size and the dark bill tip to flip the coin. If the  
first and third birds had been even remotely same-sized, I'd have  
gone the other way.

I guess I have a meta-question here. I'm using Sibley as my primary  
guide. It seems to be well received. One thing I've wished for is a  
size range on a bird, not just a typical size, given that I don't  
seem to ever meet a bird of typical size... (grin). But are there  
better guides? Or is this just a case of learning how to translate  
"book" to "see" and experience? Is there a better guide I could be  
using?

I appreciate the feedback and patience. As I've gotten serious about  
this, I've been really enjoying the chase since I got sick and told  
work I was taking my life back. I realize doing it solo is tough, but  
this group is a great tutor, and until recently, going on group  
outings was basically not possible for me. That's going to change,  
trust me...


-- 
Chuq Von Rospach, Architech
[[email protected]] -- http://chuqui.typepad.com/



And lo, though I travel through the valley of the archetypes, I shall  
fear no evil, for I know that the author can't kill me off for at  
least another 150 pages, no matter how stupid or trite I become, or  
he ruins the book.



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