ML44053581

Age

Not specified

Sex

Not specified

Observation details

Found by my wife, Linda, in front of our house. Initially identifying it as a Peregrine Falcon, I asked other birders for help determining the subspecies. Based on the photos in this report, John Schmitt, noted raptor illustrator for several field guides, sent me the following comments: "I regret to inform you that your bird, photographed on 26 January 2012, is a hybrid. For me it is very interesting, but must be a bit of a let-down for you and Linda. The falcon in your images is one of the most popular hybrid combinations in the sport of falconry: a Peregrine-Prairie Cross. In this instance the Peregrine parent was most likely of the Peales race. All Peregrine-Prairie crosses show the bright, short supercilliary line above the eyes, which is also prominent in all Prairie Falcon plumages, and to a much, much lesser extent in some adult Peregrines. The narrow black malar bar/moustache is also typical of all PeregrineXPrairie hybrids, but is also very like that of the "tundrius" Peregrine. Consequently, there is no one that I know who wouldn't suspect that this bird was anything other than a Peregrine in a fly-by view. The markings of the underparts of this "cross" show a marked tendency to be spots, with the Prairie Falcon tendency to be larger and more concentrated at the sides, much like what your bird shows. The majority of PeregrineXPriaries show spotting, which again, is the Prairie influence. Many hybrids will show barring at the sides, but even then they are thicker than in a Peregrine, and tend to be concentrated, producing a Prairie-like dark area. Your bird's markings are quite heavy throughout, including into the chest and almost into the throat, which is the result of the Peale's Peregrine influence. In contrast, the PeregrineXPrairies where the Peregrine donor is one of the lighter races, the chest is often clear as in both parents, and the belly will be more or less spotted, but seldom finely barred." "I cannot see the bird's nape in any of the images you provided, so I cannot see the "brown retained immature feathers" that you referred to in your age assessment. But I offer the following explanation: all PeregrineXPrairies show rufous mottling at the nape, especially the crosses involving Peregrine parents of lighter races. In addition, I have observed many Peregrines, both living wild birds and museum specimens, that have some rufous nape mottling. So this trait is frequently expressed in hybrids. Furthermore, in first adult plumaged falcons, the retained brown juvenile feathers are frequently confined to the "elbow region" of the upper wing coverts and the upper rump(typically concealed on perched birds). Also, some retained juvenile feathers will be found in the lower belly, flanks/sides,crurals(leg feathers), and underwing coverts. But these are usually few and visible only under ideal conditions. I don't believe I have observed retained brown juvenile feathers in the napes of any birds that are otherwise in mostly adult plumage. So I think the brown nape feathers that you observed were not retained juvenile, but simply a trait expressed in this hybrid." "The appearance of the upper parts of the majority of PeregrineXPrairies is nearly identical to a Peregrine. The few diagnostic differences that do exist are visible only under ideal conditions, ie; in the hand. The upper parts of some of the hybrids with Peregrine donors of a lighter race may have a "pinkish" cast, but would not be useful in the field. In the case of your bird, its upper parts appear "Peregrine gray", again the result of the dark Peale's influence. So. if this bird flew past us presenting only a dorsal view, we would be left with the strong impression of a large dark gray falcon with a prominent, but narrow, black mustache--an adult Peregrine. Who among us would detect the short bright white supercillium, literally the only visible trait in that perspective, that could raise a red flag."

Technical information

Model

Canon EOS 50D

ISO

400

Focal length

400 mm

Flash

Flash did not fire, auto

f-stop

f/9.0

Shutter speed

1/800 sec

Dimensions

1118 pixels x 1677 pixels

Original file size

420.64 KB