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Western or Island Scrub Jay? (1 Viewer)

LzyPhotographer

Well-known member
I took these in San Diego - the question is what kind of Jay is it? From what I looked at to identify it, I thought it was the Island Scrub Jay. Marysan who knows a whole lot more than I do, is wondering... what say ye?
 

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Island Scrub Jay occurs ONLY on Santa Cruz Island, in the Channel Islands. Main characters are the larger bill (significantly larger than in your photos) and the blue undertail coverts, where the bird in your photos has whitish/greyish u.c.s. The throat streaking is pretty distinct, indicating one of the coastal subspecies, although the difference is not as clear in your bird as Sibley would have it.
 
Interesting one. There may be more to it than Charles suggests, courtesy of the local endemic Torrey Pine (Pinus torreyana).

This pine grows in only two localities, San Diego (Torrey Pines State Reserve), and Santa Cruz Island; its seeds are dispersed by Scrub Jays, and are the main food for them certainly on Santa Cruz, and probably also within the SD TPSR. The nut shells of the Torrey Pine seeds are much harder than those of other pines; this has forced the evolution of the heavier bill of the Santa Cruz Scrub Jays.

It is also reasonably to expect that Scrub Jays in the SD TPSR also need stout bills to deal with Torrey Pine seeds, and could prove to be an (as yet undescribed?) new race of Scrub Jay, which has developed similarities to the Santa Cruz birds through parallel evolution. It is likely though not to have been able to evolve so much genetic distinction as the island birds, as they are not isolated from other 'normal' Western Scrub Jays elsewhere in California, so with genetic mixing still going on.

Certainly worth more investigation, though.

Michael
 
Checking further to the above, I read there's 15 described races of Western Scrub Jay, so the San Diego TPSR ones almost certainly are a known, described race. Unfortunately, my books don't give a full listing of all 15 races.

Michael
 
Michael Frankis said:
Checking further to the above, I read there's 15 described races of Western Scrub Jay, so the San Diego TPSR ones almost certainly are a known, described race. Unfortunately, my books don't give a full listing of all 15 races.

Michael


Here they are.

Aphelocoma californica californica
Aphelocoma californica inmanis
Aphelocoma californica caurina
Aphelocoma californica oocleptica
Aphelocoma californica cana
Aphelocoma californica obscura
Aphelocoma californica cactophila
Aphelocoma californica hypoleuca
Aphelocoma californica nevadae
Aphelocoma californica texana
Aphelocoma californica grisea
Aphelocoma californica cyanotis
Aphelocoma californica remota
Aphelocoma californica woodhouseii
Aphelocoma californica sumichrasti

take with a grain of salt as more work needs to be done and some may result in the end to be consubspecific.

Steve

:news:
 
Michael Frankis said:
Hi Steve,

Thanks - do you have distributions for those by any chance? Is there one endemic to the immediate San Diego area?

Michael

Hi Michael,

I don't have them for all. However, the only ones that I've ever run across cited for southern California are races californica and woodhouseii seeming to have intermediate forms at their range limits of which, unfortunately, I am not sure.

Steve
 
Thanks everyone! I'll change the name on the gallery pic to Western.

Charles, I do see the difference in the blue undertail coverts now.

Michael, this bird was about a mile or so away from the Torrey Pines reserve...
 
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