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"Darker" Red-tails

posted by Jerry Liguori at
on Wednesday, January 4, 2012 

Western Red-tailed Hawks show a continuum of plumages from whitish and lightly marked on the underbody to completely dark. I can't possibly show all the variation from light to dark in a blog post or even in a full-length article, so I just wanted to discuss "darker" adults. Many Western light-morphs (top left) are rufous-toned underneath with typically marked patagials and bellies, but some are rufous-toned with minimal bellybands (top center). A few are strongly rufous-toned with typical bellybands (4th bird on top by Vic Berardi).

Note the rest of the birds shown have varying bellybands and apparent patagials until you see the 2 birds on the bottom right, which are typical dark-morphs. One being rufous-chested, the other solid dark. The term rufous-morph, or "intermediate-morph", is used to describe birds that are dark underneath with slightly paler rufous chests, but these birds are often difficult to tell from solid dark birds in the field. However, would you qualify some of the other birds in this collage as rufous-morphs? I wouldn't argue.

Where do you draw the line? I tend to call birds that are nearly completely dark underneath with solid bellybands and masked patagials "dark-morphs", and birds with streaked bellies "rufousy light-morphs", or "rufous-toned light-morphs"...if you take the term "rufous-morph" out of the equation. Confused? Regardless, there are just a bunch of birds out there that can't truly be categorized to morph.....or race in certain cases (that is for the next blog entry, and more interesting to me). Anyway, I don't get too caught up in trying to pin a label on every Red-tail, it can drive you crazy...or crazier in my case.

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3 Comments:
Blogger Jay Bird said...

Great post. Acquired a copy of your book "Hawks at a Distance" and I expect it to be an invaluable identification aide in the years ahead.

January 5, 2012 at 8:59 AM  
Anonymous Jerry Liguori said...

Thank you Jay Bird -- that is great to hear, hope you like the book and glad you like my posts. More raptor posts to come. And if you search my name in the archives, the other raptor posts should show up if interested.

Jerry

January 5, 2012 at 5:24 PM  
Blogger Bryce said...

Red-tailed Hawks! Great post. As you know, I am extremely interested in RT races and morphs. I actually photographed a "rufous/intermediate" morph last week. Well, that is what I called it at the time. It was a nice rufous toned bird with a slightly darker belly band, much like the bottom bird 2nd from the right. I called it rufous because of the color, but perhaps it was a dark morph.

I'm looking forward to the next post. Thanks Jerry.

Bryce

January 6, 2012 at 10:40 AM  

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