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Harlan's traits

posted by Jerry Liguori at
on Saturday, November 23, 2013 

A recent discussion spurred this post. Yes, it true that light-morph Harlan's are snow-white below, but some can and do have buffy or rufous tones on the underside, especially the leggings. Brian Sullivan and I show examples in a 2009 Birding magazine article, but here are some more examples. Remember Harlan's overlaps in plumage, and interbreeds with other races of Red-tailed Hawk, so they can show traits that are normally associated with other races (as do all Red-tails -- i.e. a dark or light throat can be shown on both Eastern and Western). Consider that juvenile Harlan's (especially light-morphs) can have tails that look identical to other races, that is telling in itself. I tend to call Harlan's that show traits associated with other races, or lack all the classic Harlan's traits "Harlan's variants" instead of "intergrades." I also refer them to them as "Harlan's-types" -- essentially, it is a Harlan's of some sort. Since we really don't know the extent of natural variation any more than we know the extent they interbreed (but we do know variation and intergrading does occur), identifying a definite intergrade is very tricky. If a bird shows classic traits of more than one race, then the intergrade argument may have more validity. Or, another good example could be a Harlan's-type with a fully red tail. However, many "pure" Harlan's have varying amounts of red in the tail, or rufous breasts, so a Harlan's that fits the mold in every way but has a degree of red in the tail is simply a "Harlan's", and to call such a bird an "intergrade" is a huge leap.

It is hard to draw a line between what is normal variation and what is an intergrade, and there are many birds out there that are just too difficult to classify. Anyway, here are some examples of Harlan's with atypical traits such as colored leggings or mostly red tails…enjoy.

20 Comments:
Blogger Jerry Liguori said...

Forgot to mention - note the 2 retained juvenile outer primaries (P9 & 10) on the left wing of the first bird. They are banded out to the tips like most juvenile Harlan's outer primary feathers. Also note that it has only one retailed juvenile outer primary on the right wing. Sometimes the molt is not perfectly symmetrically timed.

November 23, 2013 at 8:19 PM  
Anonymous Anonymous said...

I am learning that the variability of Harlans is so encompassing, that it can be very difficult, unless you get the proper views or photos, to ID them correctly as Harlans.

Thanks Lig,for these "learning/teaching" posts!

Pete Gustas

November 24, 2013 at 5:32 AM  
Anonymous Ron Dudley said...

A complicated subject well explained, Jerry. I enjoyed the read, and the photos.

November 24, 2013 at 6:06 AM  
Blogger Jerry Liguori said...

Thanks Ron & Pete!

I have other posts on the same or similar topic that would make all of us shake our heads?

November 24, 2013 at 7:07 AM  
Blogger Bryce said...

Great post. I'm going to be referencing this information in many many conversations, I'm sure. Keep the great posts coming. This blog is the best!

November 24, 2013 at 9:22 AM  
Blogger Jerry Liguori said...

Thanks Bryce -- sometimes I have you in mind when write these posts. I know you are an ID freak! I'm very glad you like the blog, it makes it worth it for me to know people enjoy it and learn from it. That is the exact reason I started it.

November 24, 2013 at 1:21 PM  
Anonymous Hatem Gomaa said...

Jerry,
how would you classify this color phase here?

http://www.digital-images.net/Images/Raptors/Red-Tail/Flight/DarkMorph_Red-Tailed_Hawk_5565.jpg

Normally it's listed as a "western dark morph". Could this be a Harlan's despite that red tail? And where is the line between western and Harlan's, or is there one with the overlapping?

November 24, 2013 at 7:03 PM  
Blogger Jerry Liguori said...

Thanks Hatem, Beautiful bird! It is a dark-morph Western, it shows all the classic traits. Some people split hairs and call birds with obvious rufous chests and underwing coverts "rufous-morphs", but since they are all-dark underneath regardless, I just call them dark-morphs. This one is different since it barely has a contrast at the chest and the underwing coverts mask the patagials for the most part....but there are some that would put a label such as "dark-rufous" or dark-intermediate" but I think that introduces confusion, especially since there is a complete cline from light to dark. Just the way I feel. I study plumage minutiae intensely, but don't like to confuse people who are just simply trying to learn, so I don't get too detailed in my books or on the blog.

November 24, 2013 at 8:00 PM  
Anonymous Hatem Gomaa said...

Thx, Jerry. Forgive me, you know us easterners with these dark RTs! So when I look at this bird here (ID'd as a Harlan's) and compare it to the bird in the previous photo, the only difference I see is the red tail.

http://farm5.staticflickr.com/4053/5129329306_fae10c5267_z.jpg

This bird also seems to have some brownish color with the dark and the bands on the flight feathers are quite similar. So is it safe to say in this case, what distinguishes the two is just the color of the tail? Or is there something else?

November 24, 2013 at 8:49 PM  
Blogger Jerry Liguori said...

Well, tail pattern definitely is a factor in telling dark Harlan's from Western. So is body color, amount of mottling on the chest, location in certain cases, and other factors. And of course, it may take more than one photo to ID a bird to race, and there are lots of misidentifications on the internet.

November 25, 2013 at 12:36 PM  
Blogger Jerry Liguori said...

Coincidentally, a friend (Jim Lish) just sent me a photo of the 3rd bird down that he took today! Same exact bird that Brian Sullivan photographed last year. Crazy, two people photographing the same bird years apart. I know of a few instances where this has happened and co-authored a paper on one a while back. I like when this stuff happens

November 25, 2013 at 12:41 PM  
Blogger D Myhr said...

Light morph Harlan's are quite rare in the Okanagan Valley,BC. Jerry, you ID'd one for me that I saw this spring here in Kelowna(Krider's vs Harlan's blog). C. Siddle has ID'd another one in a Blog of his from Vernon,BC. Common are Light, then intermed.(rufous) and rarer- dark(brown) morphs of the B.j.calurus. In the fall, the Harlan's migrate into town and compete with the locals for food and viewing trees. They are darker, generally a dull black to dusky black, with weak to moderate white chest patches and striations under the throat area. The dorsal tail-view is classic grey to dirty white, with a terminal band of grey, dark grey, or mottled red and dark grey.
So that said, the photos of the RTs by others would fall into "my" Intermediate( rufous) morph,Western and the other is a classic/classy Harlan,dark morph. Beautiful photos. There, I've stuck my foot in-the-pie.

November 25, 2013 at 4:43 PM  
Anonymous Hatem Gomaa said...

Thanks, Jerry. Must admit, those really dark birds are tough, but so aren't the ones above. It's easy to say "Harlan's", especially the super dark brown/black birds with the light, banded or non-banded tails. Once you start getting into the ones with red tails and lighter colors, it becomes much more difficult to distinguish them from westerns and vice versa. To me, the first identifiable trait is the light tail. I see a light or non-redish tail and it really can't be any other race but Harlan's (excluding juveniles and leucistics, of course). But then you look at all 4 pics you've posted above and at a relatively good distance, the first one looks eastern, the next three look Kriders! The only thing that would make me second guess the 2nd and 4th birds is the base of the tail. It's dirty and blotchy which seems to be a Harlan's trait. Other than that, It's pretty difficult and challenging to nail it dead on, even off of photos like these let alone at a quick glance through binos at a 1/4 mile.

November 25, 2013 at 5:08 PM  
Blogger Jerry Liguori said...

Thanks Daryll -- You live in a great area for lots of variation! Please keep sharing your pics and opinions, it is most welcome and appreciated.

November 25, 2013 at 5:10 PM  
Blogger Jerry Liguori said...

Hatem -- You nailed the whole point of this post!

November 25, 2013 at 5:11 PM  
Anonymous Hatem Gomaa said...

That first one at the top is still buggin' me........it has everything that makes up an eastern red-tail, except maybe, 1 really obscure thing that makes me pause a bit and that's the faint markings on the tail as well as the faint sub-terminal band but we can solve that, too.
So it has all these eastern traits:
1) the ultra white throat
2) light chest and underbelly
3) one of several classic belly bands markings seen on easterns
4) slightly ruffous/creamy colored leggings
5) typical uniform barring on secondaries and primaries
6) creamy under-wing converts with exact dark brown streaks
7) dark carpals and exact patagials.
Problem with the tail could be faded adult? So what makes that a Harlans?
Gimme back my bird! :)

November 25, 2013 at 6:27 PM  
Blogger Jerry Liguori said...

The first one is tough -- check out the snow-white chest, white around the eye, (as you said "ultra white throat", very Eastern-like bellyband but thick, separated streaks, mottling at the base of the tail (hard to see), brown head (instead of golden), and the outer primaries are retained juveniles that are banded to the tips. The snow-white chest or body is the first thing to look for.

By the way, borealis and Harlan's DNA are nearly identical so its no mystery why light Harlan's look very eastern-like! I had made the statement that I thought Harlan's were more likely to be closely related to borealis than any other race almost 10 years ago and got laughed at.

One more thing, I didn't want to mention this because I wanted people to look at each bird as a separate ID challenge, but the bird in the first two photos is the same bird.

November 25, 2013 at 6:56 PM  
Anonymous Hatem Gomaa said...

Yes, I see all that, now. Incredible. Now that you mention it that chest does look quite a bit more whitish than the lighter cream of easterns. And the white throat patch seems to blend into the chest as if they're both identical in color, whereas in easterns the white throat is much whiter and stands out a bit from the chest (for the most part). And good spot on those retained outer primaries, I missed those! Clear as day, now. Amazing that's the same bird in the two pics but you can see that now. The difference form the ventral to the dorsal is quite extreme when seen them individually and can easily fool you as opposed to seeing a combination of the two. Good stuff. Thx, Jerry.
The bird in the last pic along with the fourth one offer the same challenges because of similar plumages and that uniform barring,but the birds in the 3rd and 5th photos are a little easier because of that prevalent, messy, motling mush-mush markings on the secondaries and primaries instead of those organized bars and bands. Is it safe to use that motling on the flight feathers (and even the tails) as a dead give-away for Harlan's? IIRC, I don't think any of the other races have that.

November 25, 2013 at 8:22 PM  
Blogger Jerry Liguori said...

The mottled flight feathers is great for Harlan's. Of course many don't show it, and a few birds of other races show unbanded flight feathers (which look Harlan's-like). But yes, for the most part it is an adult Harlan's trait and when shown is a great trait to help ID them.

November 25, 2013 at 8:43 PM  
Anonymous Hatem Gomaa said...

Excellent. Thanx, Jerry.

November 26, 2013 at 2:07 AM  

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