[obol] Re: Sooty or Red Fox Sparrow
- From: Jack Williamson <jack.williamson.jr@xxxxxxxxx>
- To: David Irons <llsdirons@xxxxxxx>
- Date: Sun, 22 Dec 2013 09:20:40 -0800
Dave, thank you for replying. Your explanation along with the BirdFellow
images went along way to help me develop a better understanding of the
differences between the Red and Sooty subspecies. I'd be very happy to
contribute my photos to your gallery. I'll send you a download link in
another email. Thanks again.
On Sat, Dec 21, 2013 at 10:34 PM, David Irons <llsdirons@xxxxxxx> wrote:
> Jack,
>
> The bird in the bottom two images is clearly has many of the
> characteristics of a Red Fox Sparrow. Those include a somewhat streaked
> rather than unstreaked mantle (back); pale tips to the median and greater
> coverts, which creates very weak wingbars, something that I've never seen
> in a seemingly pure Sooty Fox Sparrow; a reddish "C" shaped crescent that
> to some degree frames the auriculars (cheek area) and contrasts noticeably
> with a mostly gray face. Also, it has a bright russet tail and rich reddish
> wings (note that many Sooties, particularly the birds that winter away from
> the outer coast, are quite reddish in the wings and tail–see last paragraph
> below).
>
> I've been involved in a number of recent online discussions about birds
> that resemble yours. I am of the opinion that these birds are more likely
> Sooty X Red intergrades rather than "pure" members of one of the subspecies
> assigned to the Red Group (*P. i. iliaca* and *P. i. zaboria*). While
> James Rising states in his sparrow book that the eastern *iliaca* and
> western *zaboria* cannot be reliably separated, I've had Alvaro Jaramillo
> tell me that he thought a bird that looks like yours was *P. i. zaboria.*
>
> In preparing the BirdFellow ID photo gallery for Fox Sparrow (link below)
> I selected from Red Fox Sparrow images taken from Michigan, Manitoba, and
> Alaska. Presumably, the more easterly birds are *iliaca* and the Alaska
> birds are *zaboria. *Frankly, I can't see much difference in their
> appearance, thus I'm inclined to side with Rising. Bright and contrasty as
> it is, your bird is still not as bright and contrasty as a classic Red Fox
> Sparrow.
>
> http://www.birdfellow.com/birds/fox-sparrow-passerella-iliaca#/idPhotos
>
> *Here's what I see that leads me to believe that your bird is an
> intergrade: *
>
> One of the first things that I notice is the dusky wash on the lower
> flanks. When I look at presumed pure Red Fox Sparrows the base color of the
> flanks is white or off-whte with fairly crisp dark streaks with white
> showing through in between. They don't show any blurry dusky wash on the
> flanks and the streaking is not blurred out as it is just above legs on
> your bird. The second thing that I looked at was the contrast in the back
> streaking. Red Fox Sparrows typically show fairly strong contrast between
> colder medium-gray and dark reddish brown on the back, thus they look very
> streaky on the mantle. Your bird is streaked on the back, but the contrast
> between the warmer olive-grays and dull reddish brown is not nearly as
> obvious and the back seems more con-color at a quick glance.
>
> One of the real keys is the head and face pattern. I see some things about
> the head and face pattern that don't fit a pure Red Fox Sparrow. First, the
> crown is rusty brown and doesn't seem to have much, if an gray feathering.
> Red Fox Sparrows have mostly gray crowns. Secondly, Red Fox Sparrows
> normally have a big patch or crescent of red in the auriculars, bordered
> below by fairly obvious wedge or triangle of white (may have some red
> mottling within) with the triangular reddish brown malar mark below that.
> Your bird has a suggestion of the white wedge, but it seems less obvious
> than it is on most of the Reds in the BirdFellow gallery. Your bird also
> shows less red in the auriculars than the birds in the BirdFellow gallery.
> There is essentially no red right under the eye, which all of the Reds in
> the BirdFellow gallery show. Images #6 and #11 in the BirdFellow ID gallery
> offer the best examples of the white wedge and this field mark seems to be
> more obvious in eastern birds and less apparent in the birds photographed
> on Alaskan breeding grounds (#4 and #5). The Birds of North America (BNA)
> Online account suggests that westerly Reds (presumably *zaboria*) are
> more gray on the head and nape, which seems to be accurate if you compare
> the Alaska and Manitoba birds in the BirdFellow gallery (link above).
>
> It is always important to consider age-related or seasonal (after hatch
> year) variations, as that could account for a winter bird appearing to be
> duller than adults on the breeding grounds. According to the BNA Online
> account, formative plumage (first winter) and basic plumage (after
> second-year in winter) plumages are indistinguishable except for molt
> limits in the flight and tail feathers. I don't see any obvious molt limits
> in your bird. Mike Patterson or Dennis Vroman (who are banders) might see
> something that allows them to more positively age this bird, but I don't
> see anything that leads me to believe that it's a hatch-year bird. Also,
> the BNA Online account states that there are no obvious differences between
> the basic and alternate plumages in Fox Sparrows.
>
> Another thing to point out about your bird is the streaking and spotting
> on the underparts. I think that your bird is more heavily streaked and
> spotted below than a typical Red Fox Sparrow. If you look at the photos of
> Reds in the BirdFellow gallery you might notice that the spotting/streaking
> fades out on the lower breast/upper belly with much of the belly being
> white and unmarked. On your bird, the streaking/spotting extends way down
> the underparts, with only the extreme lower belly and vent area being
> unmarked.
>
> In looking at a bunch of images I noticed one other thing. Sooty Fox
> Sparrows often show quite a bit of red in the wings and tail and are highly
> variable in this regard (I co-authored a photo essay on this topic that
> appeared in the March 2012 issue of *Birding* -- Vol 44:2). However, in
> looking at the wings and coverts of Sooties, I noticed that the median
> coverts are typically a bit duller and sometimes less reddish or more
> earthy brown than the greater coverts and secondaries. Conversely, the
> median coverts, greater coverts and folded flight feathers/secondary edges
> look similarly reddish in all the BirdFellow photos of Reds. Your bird has
> noticeably duller, less reddish median coverts.
>
> Finally, thanks for sharing the photos of this very dapper bird. Fox
> Sparrows continue to offer of one of the best case studies when it comes to
> speciation. The murky line between species and subspecies becomes really
> blurry when you start studying Fox Sparrows. Thankfully, they are very
> attractive birds and generally cooperative if you like to photograph them
> (I certainly do). With your permission, I would love to add these two shots
> to the BirdFellow ID gallery for Fox Sparrow, as they are very instructive.
>
> Dave Irons
> Portland, OR
>
>
>
>
> ------------------------------
> Date: Sat, 21 Dec 2013 18:19:42 -0800
> Subject: [obol] Sooty or Red Fox Sparrow
> From: jack.williamson.jr@xxxxxxxxx
> To: obol@xxxxxxxxxxxxx
>
>
> As a result of twice receiving comments on photos I've posted of Fox
> Sparrows over the past year, I am now well conditioned to regularly look
> more closely at this species than I used to. I just wish I could the same
> thing about Gyrfalcon :-) Nevertheless - we had a Fox Sparrow show up this
> afternoon that clearly contrasts to the one we regularly enjoy watching in
> our backyard.
>
> Thank you in advance for any thought you might have on this topic.
>
> http://www.jack-n-jill.net/blog/2013/12/sooty-or-red-fox-sparrow
>
> --
> Jack Williamson
> West Linn, Oregon
>
--
Jack Williamson
West Linn, Oregon
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