[obol] Re: Pale Red-tail in CO
- From: Craig Miller <gismiller@xxxxxxxxx>
- To: "Richard W. Musser" <mussermcevoy@xxxxxxxxx>
- Date: Sun, 1 Mar 2015 10:58:39 -0800
Hi Richard,
All your points are well-taken, and I pretty much agree with everything you
say. However, the what I was wondering (and seems to be missed, or am I
missing something?) is if we do take the edgy step of conjecturing, why
doesn't this bird fit Krider's better than Harlan's?
Craig
On Sun, Mar 1, 2015 at 9:39 AM, Richard W. Musser <mussermcevoy@xxxxxxxxx>
wrote:
> Hi Craig,
> I think we can call this a red-tailed hawk, but assigning a
> subspecies designation to migratory RTs, is simply a guess (we have no way
> to prove this one way or another). I know birders that are looking for
> photos of various odd appearing RTs with assigned subspecies---and then
> comparing the pictures. But my point is: There isn't a way (at present) to
> clearly define what a Harlans Rt really is. When we define a bird species
> (or subspecies), it seems to me that we are looking for aspects that are
> the same; but harlan's tails are all different, as is much of their other
> feathering. So exactly where do these harlans originate? When I think back
> to the article with all of the oddly appearing, "Harlans tails"----I
> realized that with all of my, "raptor looking" experience in Alaska for
> over 25 years, I was never able to locate a nesting pair of harlan's
> red-tails. Some of these raptor research scientists have documented these
> "odd tailed harlans" moving into Alaska on spring migration (and I too have
> seen this at the same location)----but as far as I know, the exact region
> of their nesting isn't completely known.
> Many of our raptor species are much more narrowly defined---our
> Harris's hawk, prairie falcon, NA goshawk, and Ferruginous Hawk (for
> example) show little variation----but our red-tailed hawks, Swainson's
> hawks, and roughlegged hawks are buteos that are still very confused. It
> may be that Rts are composed of two or three different species that can
> interbreed----but have only been doing this for a relatively short time
> period. Humans have altered the landscape of North America from the time
> that seeds were brought here by Columbus, and later when we cut down much
> of the forest east of the Mississippi---and doing this may have opened
> pockets of isolated buteo species, or altered food supplies. Red-tailed
> hawks also show great variation in size and weight, and I clearly recall
> trapping a "butterball fat" adult male Rt that weighed only 28 oz., and
> later that week, at the same location, capturing a large female at 66 oz.
> Both of these individuals looked like "classic" adult red-tailed
> hawks----but with such a large disparity in size, it is very unlikely that
> they would pursue the same sort of quarry. So how alike are they? Do these
> little males breed with these huge females?
> An avenue that is open to explore the Harlans Rt----is to obtain
> photos of adults with young---and then to moult a few of those
> youngsters---to see how they appear. It may be possible that these photos
> already exist from falconers taking this raptor within Alaska and
> Canada---but I have no firsthand knowledge of this, and only suggest it as
> a method.
> I commend all of those that are trying to figure out this confusion,
> but it may take DNA analysis for scientists to untangle Bueto Jamaicensis.
> Best regards, Dick Musser (4 mi. NW of Vale)
>
>
> On Saturday, February 28, 2015 10:59 PM, Craig Miller <
> gismiller@xxxxxxxxx> wrote:
>
>
> Why isn't this a Krider's?
>
> Craig Miller
>
> On Sat, Feb 28, 2015 at 3:31 PM, Tom Crabtree <tc@xxxxxxxxxx> wrote:
>
> Chuck,
>
> It would be nice to have better shots of the tail, but it is either a
> light phase Harlan's Hawk or a leucistic Red-tail. It looks an awful lot
> like a white-headed, light-phase Harlan's in an article by Brian Sullivan
> (who I hope will comment on this) and Jerry Liguori in the March 2010
> Birding. http://www.aba.org/birding/v42n2p30.pdf This is whiter than
> the Harlan's I have seen but I think it still in in the range of that race.
>
> Tom Crabtree, Bend
>
> -----Original Message-----
> From: obol-bounce@xxxxxxxxxxxxx [mailto:obol-bounce@xxxxxxxxxxxxx] On
> Behalf Of Charles Gates
> Sent: Saturday, February 28, 2015 12:19 PM
> To: obol
> Subject: [obol] Pale Red-tail in CO
>
> I'm going to post some links to some Red-tail photos I received. Please
> feel free to comment. The photographer was Debbie Goodman and the location
> is just NW of Redmond, Oregon. The date was 2/23/15.
>
>
> https://www.flickr.com/photos/124095129@N06/16673978732
>
>
>
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