Dark Hawk ID Challenge
A few days ago, I spotted a dark hawk flying over the Ballona Creek. I first saw the bird at a long distance. The coloring suggested a turkey vulture (white underwing, white undertail, otherwise dark), but it wasn’t wobbling. I thought it could be a Zone-tailed (would be a 5MR lifer), but it was too far away to tell. Frustratingly, it went out of my view.
About 30 minutes later, I found what I assume was the same hawk perched on a low snag along the Ballona Creek bike path. The back and chest/belly were all pretty uniformly dark brown, with a little white splotching on the wing. It had yellow legs and pale eyes. The bird flushed, and I saw that its underwing and undertail was white with faint grey barring. The bird landed on the ground in the middle of a large field scattered with tall grasses. After 5 minutes, it moved 50-70 yards and landed on the ground again, this time out of view.
I found the landing on the ground to be the most notable behavior I observed. I couldn’t recall ever seeing any Red-tailed Hawks settle on the ground in this field before. And this bird did it twice. That, with the dark coloring, had me thinking that I had found something other than a dark western Red-tailed Hawk. But I don’t have the birding chops to make an ID.
On top of that, my photos that first day were pretty bad. They were taken with a pocket zoom camera I bring along on bikes rides. The photos did show some barring on the white sections of the underwing and undertail. You could see that the upper undertail was dark. And the back and upper wings were, other than a few white speckles, uniformly dark dark brown.
I posted my photos and description to LACO Birds listserv (an invaluable resource for anyone, but especially those like me who don’t use facebook or eBird alerts. Indeed, I love local bird sighting listservs. Anytime I travel in the U.S., I look up the local birding listservs). The reactions were both unanimous (“better photos would help”) and mixed (Zone-tailed Hawk, dark morph juvenile Western Red-tailed Hawk (calarus), dark morph juvenile Red-tailed Hawk (Harlan’s), and dark morph Ferruginous Hawk were all mentioned).
Seeking better photos and a more certain ID, I rode out to the spot a couple of days later. I found the dark hawk again, perched on a low snag in the same field. Once again, just after I started to take pictures, it flushed. And just as before, it flushed to the middle of the field and landed on the ground, out of view. I biked around the area, trying to re-find it. There were at least 4 obvious (though varied) Red-tailed Hawks in the field. One had a dark belly, but a rufous tail.
I re-found the target dark hawk after 20-30 minutes: in the middle of the field on the ground. It eventually flew to a low snag perch closer to the bike path. The bird was still all dark dark brown, but more white mottling on the upper wing and some white streaking on the chest were apparent. When it flushed, I was able to get better looks at the underwing. The barring on the white underwing areas was more obvious today, and the dark portion of the underwing looked more mottled with white. Again, it flew to the middle of the field and landed on the ground. None of the obvious western Red-tailed Hawks around (at one point I saw 3 perched and 3 soaring at the same time, so there were at least 6 others in the area) ever landed on the ground.
Birders far more expert in hawk ID than me felt better about calling the bird a Harlan’s Red-tailed Hawk after the second round of photos. Features that these folks noted as supporting a Harlan’s Hawk ID were the uniform dark brown color, the dark upper undertail, and the pale iris. A couple of other birders have seen the bird, and got even better photos. My report of Red-tailed Hawk (Harlan’s) was confirmed in eBird, which I take to be the stamp of approval on the ID. Not everyone agrees, though.
Harlan’s Hawk has been a separate species in the past, but is now considered a subspecies of Red-tailed Hawk. They breed in Alaska and northwestern Canada in taiga. Many of them winter in the central U.S. plains. A Harlan’s Hawk is a good find for L.A. County. There are a couple of reports of Harlan’s Hawk in the Antelope Valley (northern L.A. County over an hour from my house), a 2017 report from Long Beach, and a wintering Harlan’s Hawk in the very same Ballona area in 2013-2014. They undoubtedly occur more frequently, but the variability of Red-tailed Hawks means they are likely overlooked. The best comparison of Harlan’s Red-tailed Hawks with Western Red-tailed Hawks is here.
I saw the hawk again on Christmas Eve in the late afternoon. Nothing had changed. I found it perched on a low snag not far from the bike path. It flushed as soon as I got off my bike and peered at it through binoculars. It flew to the middle of the field and landed on the ground. Maybe it will stay all winter like the 2013-2014 bird, and I can study it a bit and maybe get the bird to do a close flyover in good lighting.