This is part of an older post from The Utah Birders Blog I wanted to share. It is a neat bird and worth a second look! Thanks again to Steve Christensen for sharing the photos with me. "Click" on photos to see larger versions
Hybridization between two separate raptor species is rare, but does occur. Typically, hybrids are the result of two similar species (from the same family) breeding together. I am aware of one Ferruginous x Red-tail mated pair in Utah with nestlings, one documented Ferruginous x Red-tail hybrid (which appears to be this same bird, but lack information regarding it), and several falconry hybrids. What makes this bird a hybrid and not a pure Red-tailed Hawk or Ferruginous Hawk? Simply put, the mixed traits of both species.
Overall the bird shows rufous underwing coverts, rufous leggings, and a prominent yellow gape like a Ferruginous Hawk. However, the tail pattern is red with multiple black bands and a broad sub-terminal band like a Red-tailed Hawk. Some Ferruginous Hawks can have nearly all-red tails but they lack symmetrical bands (pg. 67 Hawks From Every Angle, pg. 90 Hawks at a Distance). The remiges (primaries and secondaries) are Red-tail-like showing obvious banding, a broad, dark sub-terminal, and prominent dark wing tips. The brown color to the head is more similar to Red-tailed Hawk as well, adult Ferruginous have a slightly paler brownish, or grayish head. The bird lacks the dark brownish-black patagial marks that Red-tailed Hawk shows. The wing shape seems a bit lengthy and slim for a Red-tail and more like a Ferruginous Hawk, but that is subjective, difficult to say from the photos, and possibly inaccurate.
Jerry Liguori
7 Comments:
Very cool. This is exactly the type of thing I want to see. Great discussion as well. Thanks Jerry!
Thanks Bryce
Still working on getting some pics of add balls together, have too many but will post a few soon
This bird is unbelievable! Do you have any more photos of it, Jerry?
Let me check, I might....they are not my photos. I do have photos of nesting birds of two separate species. Here in Utah there are a few Swainson's nesting with Red-tails and 2 Ferrugionus and Red-tail pairings.
That's incredible, Jerry. The RT being the common denominator. Maybe these birds are capable of feeling emotions such as love? How else can you explain two birds of different sexes and species joining together to breed?
Bird love....I never considered that. I do believe animals of a certain level have emotions. They certainly react to intruders, etc. But two species breeding together could just be selective pressure in a certain area, an aggressive male wanting to breed and courting any female in the area, or some other advantageous reason? Who knows?
I know it sounds silly but it really is interesting to ponder. What drives the examples of birds mating for life such as in bald and golden eagles and other species and in these cases of unusual separate species nesting? I would think if it occurs more than just one year, it's plausible that it could be something much greater than just territoriality. There is a certain level of "bonding" (perhaps that's a better word than 'love'). But as you said, who knows.
I also think the females are much more aggressive and territorial than the males in many instances and their larger size might be a reason for that. I don't think it has a lot to do with incubating eggs and brooding chicks because that duty (or at least the incubation) is shared by both sexes like in bald eagles and many other types of raptors where there is clear sexual dimorphism. I think it was observed in city nesting peregrines that the females would kill the male in a heartbeat for whatever reason and control and dominate the entire breeding task. There has been some examples of peregrines nesting in Boston where the nesting female was violently killed by a younger female which immediately took her place. http://www.highbeam.com/doc/1P2-8278262.html
So maybe it's the females that are more pressured into breeding (for whatever reason, hormones, instincts, need for bonding, whatever) than the males? Interesting stuff to think about and I hope you don't mind the discussion, Jerry. :)
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