From the Contact Station February 2018

Red-tailed Hawk Variation

by Susan Setterberg, photos by Virginia Scott

As I have said in the past, I love winter on the River ‘S’.  Often, I can see multiple Red-tailed Hawks without setting foot outside the contact station.  There are several that perch and hunt within view, but more often I get to see what is around the River ‘S’ drive because photographers stop to ask what hawk they have in a recent photograph.

Typical Red-tailed Hawk characteristics are fairly easy: belly band, red tail, dark head and the dark patagial mark on the forward edge of the wing.  But, and that is a big but, that is not always what you see and the variation in those characteristics can make you wonder at your identification.  A perched bird will not show the patagials; in flight, the angle or the color morph might not be right to assess that characteristic.  Red-tails can vary considerably and when you have wintering young birds, they show an even greater variety of color and character variations.  Look at these recent photos taken by Contact Station Volunteer Virginia Scott
  

They are all Red-tailed Hawks.  A small fraction of the Western race of Red-tailed Hawks include Dark and Rufous morphs.  The more typical white-morph adults have the dark brown head, throat and upper parts and the lovely rufous tail, which can show some additional dark banding in some birds.   However, the white-morph juveniles can show a white throat, and a more prominent wide, dark belly band.  Variation.

Young Red-tailed Hawks may not have a red tail yet. Yet they always have what I like to think of as fine banding on their tail (7 to 9 dark bars of uniform width) compared to the other hawks we have on the refuge.  The first bird shows this banding nicely.  Well, that is true except for the Krider’s Red-tailed, which is a white morph with paler brown wavy bands on a white tail.  Though that would be a very unusual variation to see here. There seems to be an exception for every Red-tailed rule.

Now look at the rufous colored Red-tail Hawk photo.  The belly band is there, chest and legs are rufous which is typical for this morph.  If it were to fly, you could be able to see the contrasting patagial marks.  We can’t tell much about the tail from this photo.  There is a lot of white on the face and the chin suggesting a younger bird perhaps. (Don’t be distracted by what looks like a longer, Kite-like bill on this bird.  It is an artifact of the photo with a dark piece of vegetation making it look longer.)  And what about this wonderful all dark bird.  Hmmm.  There are dark morphs of the Western Red-tailed race; then there is the Harlan’s race of Red-tailed which are mostly dark morphs and rare here. Adult Harlan’s would have (usually) white streaks on the breast.  But his bird seems to have a bit of rufous in the breast.  Harlan’s tails are whitish to gray with smudgy black marks and terminal band, like this bird.  It would be great to have other views of this bird to see back patterning or if the dorsal side of the tail is rufous or white.

I have been focused on variation here; not identification. I’ve alluded to adult vs juvenile but didn’t touch at all on the notion of intergrades; those birds that have characters of multiple races or morphs.  But to sum up, belly bands are not diagnostic for the Red-tailed Hawk, though many of us are quick to say Red-tail when we see it.  Other hawk species can show this detail and some Red-tailed hawks, particularly the lighter morphs, show little or light belly bands.  On the lighter morphs, the best field mark is the dark patagial on the leading edge of the underwings for all age birds. But, your bird must be flying to see that.  If you see a red tail on the adult, you’ve got it.  And, juveniles have two-toned upper wings; paler outer half contrasting with darker, inner half.  So, your head is probably spinning right now.  Mine is.  I am no expert on Red-tailed Hawks, so I will leave the final decision on what race of Red-tailed Hawk the dark morph is, Western or Harlan’s.  Suffice to say, they are beautiful raptors with such a wide variety of plumage as to merit a close look at each one.  Be patient to see front, back and flight patterns. Enjoy the winter variation of Red-tails.  Don’t be put off; embrace it.