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White-collared Seedeater ( Sporophila torqueola ), Gilbert Water Ranch, Maricopa CountyThis White-collared Seedeater was discovered and photographed by Richard Ditch on 03 October 2008 at the Gilbert Water Ranch where the bench overlooks the southern end of Pond 7. It was also photographed a few days later by Brendon Grice and Pierre Deviche. White-collared Seedeater has been reported several times in Arizona but never
accepted on to the state list because it is an extremely common cage bird in
Mexico and therefore establishing that these are wild birds and not escapes from
captivity is difficult. Like the bird at Kino Spings last year, this bird
does appear to be of the expected West Mexican form, although that form might
also be expected to be the most common in captivity near here as well. This bird appears to be a male of the west Mexican form, sometimes considered a separate species, the Cinnamon-rumped Seedeater. The buffy underparts, rusty rump and complete black breast band separate this bird from the White-collared Seedeater of Eastern Mexico and Texas. Some authorities (Howell and Webb, 1995) lump all Cinnamon-rumped Seedeaters into a single subspecies, S.t. torqueola. Howell and Webb state that this subspecies is usually brownish-gray backed, rarely with mottled black or completely black backs. However, Birds of North American Online recognizes a split of this subspecies into two subspecies, the northerly S.t. atriceps and the southerly S.t. torqueola claiming the southern birds have black backs and the northern birds brownish-gray backs. Northerly birds are also claimed to have less extensive cinnamon rumps and smaller white wing spots. If this description of geographic variation within Cinnamon-rumped Seedeater
is accurate (note that is seems to be contradicted by Howell and Webb), then
natural vagrant seedeaters to Arizona would be expected to have grayish-brown
backs, as did the seedeater last year in Kino Springs. In the one photo
below, the back of this bird looks very dark, but exact determination of its
color probably will require a better photo. 03 October 2008, photo by Richard Ditch
07 October 2008, photo by Brendon Grice
Although not a perfect photo, this shot does show the critical condition of the feet and tail in judging whether this bird has recently been in captivity. Well cared for captive birds will show few physical signs of being in captivity, but birds poorly maintained is small cages could have telltale signs of frayed tail or wing feathers or worn nails. Of course, escaped birds that have survived long enough to have a chance to molt and recover will also show no physical signs of being in captivity. There do not appear to be any physical signs that this bird has been held in captivity. For the reasons mentioned above, this is necessary but not sufficient to any claims that this could be a wild bird.
0 October 2008, photo by Brendon Grice
07 October 2008, photo by Pierre Deviche All photos copyright by the photographer. |
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Submitted on 03 October 2008 |
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