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Swainson's Hawk update

Here's the comments from all of you regarding the identification of the Swainson's Hawk. Very informative.


No claim of this being an "expert opinion" but I think your
bird is a Swainson's.  Red-tailed's have variable white
spotting on the wing coverts and scapulars and a paler, more
golden colored, head than the rest of the upperparts.  The
tail would (obviously) be reddish on an adult Redtail and
juveniles have paler tails with more contrasting (or more
noticeable) noticeable barring.  A couple other things to
look for on Swainson's in flight is the pattern of the upper
wing and the shape of the wing tip.  Swainson's soar with
wings help above horizontal.  The very tips of the wings ate
sharply pointed and curve sharply up.  The inner wings
(Upper wing coverts) are paler than the flight feathers
(primaries and secondaries).  Swainson's also rock more than
Redtails if there is wind blowing when they are soaring.
Hope this helps.

Cliff

You should stay with your first instinct - your hawk is a Swainson's. 
The uniform back coloring is the best mark here, but you should also 
note the feet, which are rather small for a hawk this size - another 
Swainson's characteristic. The tail pattern is right for a Swainson's, 
as is the head shape and coloration and the rather large yellow cere 
(in other words, the face looks like a Swainson's). The wing tips look 
like they may be a bit short, but it's hard to say for sure from the 
photo - to me they look about equal to the tail.

The lesson in this one is that you generally shouldn't let a single 
field mark overrule an identification based on a number of other field 
marks, even if that one seems to run contrary to the others. In 
particular, I don't put much stock in the wing/tail length in our local 
buteos - it's easy to misjudge in the field (and even in photgraphs) 
depending upon the angle of view, and the differences between the 
species aren't that great. For example, one of my field guides (a very 
good one) describes the Red-tailed as "wing tips approach or just reach 
the tail tip" and the Swainson's as "wing tips reach to or beyond tail
tip." Obviously, that's not a lot of difference, and possibly a bit of 
overlap - you'd be better off trusting other, less ambiguous 
characters. In this case, it would have given you the correct i.d.

Good birding!

Mark Stackhouse

I think your hawk is a Swainson's also.  Is it possible that the angle of
the photo causes the wingtips to look shorter than in real life?  The white
around the base of the bill and the brown, unmarked back all point to a
Swainson's Hawk.

In addition, the bird's dark iris indicates that it's an adult.  An adult
dark morph Red-tail would have a red tail, not a dark brown one.

Kris

The angle isn't very good but the wings don't look longer
than the tail in to me, especially the right wing.  Even so
wing to tail ratio is variable and I wouldn't bother trying
to use it unless there is something really distinct, like
the very long tail/short wings of a Gyrfalcon.  Even if the
wings are longer than the tail I looked at photos in
Wheeler's new Raptors of Western North America and there are
photos of Swainson's with wings lightly shorter than tail,
equal to tail, and longer than tail, all of which is noted
as such in the caption.  Underwing pattern is distinctive if
seen well but it's not always possible to get a look.
What's worked well for me is to really pay attention to the
wing shape and how they hold the wings when soaring on birds
of known species.  I mostly see Redtails and Swainson's.
Redtails have wide wings with rounded tips and bulging
secondaries.  This is obvious even at long distances and in
poor light where color may not be visible.  They hold their
wings slightly above horizontal when soaring, but not as far
above as Swainson's, and the rounded wing tips do not curve
sharply up like they do in Swainson's.  Perched birds of
these species strike me different as well.  Redtails seem
chunkier, Swainson's more slender.  A juvenile Redtail,
which this bird would have to be if it's a Redtail, would
have white spotting on the wing coverts and scapulars like
this bird:
http://bailey.aros.net/nature/images/Red-tailed%20Hawk%201st%20Year.jpg.

Cliff

It looks like a Swainson's Hawk to me. There is no clear lightening along the scapulars
(the almost always telltale sign of a red-tail from behind), the tail banding is
less distinct than juvenile red-tails often show, and there appears to be molt in
the flight feathers suggesting that this is an adult bird. Were it an adult red-tail
this far along in molt it would obviously have a red tail, so the logical assumption
is that it is an adult Swainson's. It is also slightly less chunky, a little sleeker
and more lightly built, all pointing to Swainson's in my opinion. Too bad it wasn't
turned just slightly more to the side and we could expect to see a white chin patch,
but it looks like just a little patch of white is peeking above the base of the 
beak. Swainson's often have a fine but visible white face patch, as well.

As for the tail/wing length relativity thing, I find those some of the most difficult
and misleading field marks to use. So many aspects of posture, wind, balance, molt,
and other intangibles make any degree of certainty about relative lengths of various
appendages almost useless to me.

Paul Grindrod

It's not a Ferug - no feathers on legs and wrong bill.
Dark morph Red-Tails have dark undertail coverts.
Most Swainson's have a hint of white under the beak, except the darkest of 
the dark-morphs.
Swainson's have dark gray primaries.
???
I say dark-morph Swainson's. (novice opinion)

Tim Gorman

What I believe are signs of molt are the differences in color in side-by-side feathers
both on the wing and scattered across the back.  The longest (outermost) primary
on the bird's left wing is number 10. As you move towards the bird's head counting
primaries, 10 looks old (somewhat brownish and faded, a little worn and brittle,
crinkled on the edge), 9 looks old, but 8 is darker gray, slight white tip, looks
like a newly grown feather..., 7 is old and faded, 6 is darker, newer looking and
may not even be completely grown because it seems shorter, not quite proportional
to the others. The body plumage also looks somewhat non-uniform to me, some darker
feathers scattered throughout the lighter, duller browns. Again, wind and various
ruffling factors can stir up a bird's plumage to a degree, but this has the overall
feel of the randomness of molt to my eyes.
One other thing that just struck me is the posture of the bird. It seems that Swainson's
are much more likely to perch bent forward like other passerines, more so than red-tails
which often stand very erect. Unless it was a strong head wind to force the balance
forward, I would guess this was a Swainson's in part by the un-hawklike posture.

I'd be curious what some of your other responses have been. Does consensus come 
down on Swainson's?

Paul Grindrod

Some Swainson's lack the white chin, especially on the west slope of the Wind River
Mountains here in Wyoming.

Hawks, (Buteos) are tough for me.

Gorman






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