Mystery Bird: Blue Morph Green Jay, Cyanocorax yncas

What?! I know what it looks like but WTH...!

It appears that typical of beach boys, californica has been playing with yncas...!

I'm flummoxed, as so often happens.

My first thought was a jay; it has for me, a jay shape; Western Scrub Jays have a dark mask, but they also have grey over the shoulders, a white eyebrow line, and the range isn't right (if the refuge is where my map thinks it is). They've got the right sort of tail, and a light off-white underside. Maybe this is a western scrub jay without the gray shoulders somehow, and we're not seeing the eyebrow or it's not in some populations? And it's wandered a long ways? But the underside seems more light blue than off-white.

The Florida Scrub Jay would also be way out of range (and is rarer, looks like?), lighter, has a lighter gray over the shoulders and white over the eye.

I also looked at buntings, the Blue Grosbeak, but those are all blue on the underside as well, and don't have the same masking it looks like here.

I looked at bluebirds, too, and considered the Mountain (out of range, no black mask) and Eastern and Western (no mask, reddish breast extending down fairly far).

I even looked at the Black-throated Blue Warbler (talk about out of range) which has a mask, but black on the sides of wings, and just doesn't look right.

I'm looking forward to learning what this is and what the telling field marks are. Thanks :)

Well I'm pretty sure this is a blue mutation or morph of the Green Jay, Cyanocorax yncas.

There are some records of Green Jay x Blue Jay hybrids but I would expect more than just color to be evident and my beachboy jibe concerning a Scrub Jay (Aphelocoma californica) x Green Jay would fit better, however there are 13 subspecies recorded for the Green Jay, with two loose populations described- one for North and Central America (8 subspecies), and the second for South America (the remaining 5 subspecies), within which I have found varying degrees of green through blue-green photos and also white-headed variations; subspecies glaucescens and luxuosus are recorded for Texas.

The Texas populations are decsribed as non-migratory (USGS Patuxent Wildlife Research Center) however there is some restricted migration within the more tropical subspecies in Central and South America so one might wonder if one of the "bluer' tropical species wandered North...

I have read of the changes from green to blue in a Peruvian subspecies (Cyanocorax yncas longirostris) but the "blue" is really a blue-green and not as definitive as our friend above, and also the subspecies cyanodorsalis from Colombia and Venezuela translates as "blue-backed" but photos really show another blue-green variant.

If the blue (and green) was a pigmentation, a mutation could remove all the yellow pigment from the feathers, which would turn green to blue (and yellow to white) however with the exception of two species of turaco (Musophagidae) blue and green are structural colors or schemochromes and not pigments so structural changes to the feathers would be the only explanation. I would assume this change could occur in two ways: degradation or fading (state), or trait-inherited microscopic prismatic variation, which might also include a degradation of yellow pigmentation (due to carotenoids) over a structural blue coloration (i.e. varying tints of green/blue-green)- as carotenoids are acquired by birds through ingesting carotenoid-producing plants (looking out over the almost 2 feet of snow that fell here overnight, the cardinal comes to mind) a subtle change in diet could perhaps also explain a blue morph of the Green Jay.

I'm still not sure if this is a fixed morph or a random mutation, but I'm going for Green Jay, Cyanocorax yncas luxuosus as the Laguna Atacosa NWR is in the lower Rio Grande Valley.

Bluish-green variation, Rio Grande Valley, TX

Blue-green variation with white head/nape, Tamaulipas, Mexico

David -- you're suggestion that the blue color is due to the loss of yellow pigments over a structural blue fits nicely with the same phenomenon in Budgerigars. This bird is very worn, though. (Check the primary tips) Just a thought, is it possible that the loss of yellow pigment could be due to feather wear?

I do seem to recall that some authors list the South American races as a separate species, Inca Jay -- both the Ecuador and now the new Venezuelan guides do so. In which case, this should be the Green Jay, Cyanocorax luxuosus. Of course, so far the AOU doesn't seem to agree.

Paul, with regard to the loss of yellow pigmentation due to feather wear, my reference to the Peruvian example (Cyanocorax yncas longirostris) suggested as much, however the photographs in the research are really only bluish-green and not as clearly blue as in this case.

The abstract reads as follows:

We quantitatively assessed the green to blue dorsal color change uniquely demonstrated by populations of the Green Jay (Cyanocorax yncas longirostris) inhabiting seasonally dry deciduous woodland in the mid-Marañon Valley of Peru. Other subspecies in South America occupy humid habitats and are dorsally green all year. After a complete molt which ends in concert with the termination of the rainy season in March, Marañon jays have bright yellow-green backs. During the interval until the next annual molt, the dorsal plumage gradually turns to greenish-blue or blue. Starting in August and September, in the latter part of the dry season, the population breeds in this phenotype. Microscopic study revealed that fresh dorsal feathers contained a yellow pigment or pigments near the surfaces of rachi, barbs, and barbules. Older, blue feathers had many broken barbs and barbules and lacked yellow pigment. However, because the keratinous surfaces of rachi, barbs, and barbules of such feathers appeared unworn, abrasion seemed unrelated to the loss of yellow pigment. Instead, autoxidation and accompanying bleaching from exposure to sunlight are implicated in this striking color change.

from: Johnson, N.K. and Jones, R.E. (1993) The Green Jay turns blue in Peru: interrelated aspects of the annual cycle in the arid tropical zone. Wilson Bulletin of Ornithology, 105 (3), 389-398.

I believe what we have here is some form of yellow pigmentation disruption, perhaps a case of what I briefly mentioned in the so-called "leucistic" Herring Gull: either axanthism or hypoxanthism, a complete or severely reduced amount of yellow pigmentation which would alter the normal greens to varying amounts of bluish-green, or in an axanthic condition, pure blue.

I have also found an example of a Green Jay photographed in El Paso which not only shows clear blue but also has a white head and nape and white underparts including breast and undertail coverts- I think this would also support an axanthistic notion, as not only would green be absent from the body, but if the head and underparts were normally a much lighter green (read: heavy yellow overlay) or almost yellow as many "normal" jays appear, then the absence of yellow would look whitish.

Wow. That's the bluest Green Jay I've ever seen! My closest blue Green Jay is this one:

http://blog.seeingbirds.com/photos/screensize/3004

I'd be very surprised if this is an Inca Jay. More likely luxuuosus, not ynca. Yes? Scrub Jay Hybrid? Ouch! That's a mind messer.

Thanks for the pic - it's fabulous.

Another blue Green Jay from the same location:

Blue morph Green Jay from Laguna Atascosa, TX

I think the jury is still out on re-classifying the Green Jay.

For now I believe all subspecies/races are still subsumed within Cyanocorax yncas, but there is some agreement that two groups exist (there appears to be a geographical discontinuity around where the Andes are located in Colombia, and indeed this species is not listed in my Panama guide):

one in Central America comprising 8 subspecies- glaucescens (south Texas and NE Mexico), luxuosus (lower Rio Grande valley through east and southcentral Mexico), speciosus (Pacific slope of Mexico), vividus (southern Mexico to western Guataemala), maya (Yucatán Peninsula and eastern Mexico); cozumelae (off northeast Yucatán); centralis (southeast Mexico northern Guatemala, Belize, and northern Honduras); and confusus (southern Mexico and Guatemala), known as the "luxuosus group";

and the remaining five subspecies known as the "nominate group"- galeatus (subtropical zone of Colombia west of the E Andes); cyanodorsalis (eastern Colombia and northwest Venezuela); guatimalensis (mountains of northern Venezuela); yncas (southwest Colombia through eastern Ecuador and Peru to central Bolivia) and longirostris (arid upper valley of Rio Marañón in northern Peru.)

I imagine that within each group there are instances of intergrade- for example I have found some research that shows luxuosus intergrades with vividus in the Sierra de Tuxtla and Catemaco region of Veracruz.

I seem to have come into this one after it's been sorted. I just want to ask if any other Cyanocorax jays have occured in Texas.

Adrian, it appears that the Brown Jay, Cyanocorax morio, may also occur in Texas (ssp palliatus), of which there are two morphs: a brown morph tending to be more northern, and a white-bellied/white-tipped (outer tailfeathers) morph which tends to be more southern (i.e. Mexico, Nicaragua, Costa Rica, Panama).

If you look at some of the remaining species within the genus Cyanocorax, particularly the ones found in Mexico, one can see how the coloration spectrum for all species (including our Green Jay) covers any permutation we could describe...!

Thanks for the link and the answer David.

Adrian -- just to continue with the Brown Jay bit -- they have indeed occurred in Texas, just on the north bank of the Rio Grande. The last time I was down there, they were only being seen at one location (a little trailer park with a pretty serious feeder station -- I think it was called Salineno). That was in 2002, I don't have any more recent info. Neat-looking bird, though.

Adrian and Paul,

I came across this interesting article which took a look at the possibilities of hybrization between a couple of subspecies of Mexican Jay (Apelocoma ultramarina) and the Western Scrub Jay (Aphelocoma californica) because they suspected a number of traits resemble the scrub-jays.

In fact, what they found was:

"Even if low-level hybridization did occur, hybridization does not appear to be the main reason some Mexican jay populations resemble scrub-jays more than others. The scrub-jay-like traits in these populations may be due to drift, adaptation or plasticity. Alternatively, ancient hybridization, followed by selection for scrub-jay like traits in some Mexican jay populations, might have given rise to the observed variation."

Bhagabat, N.K., Brown, J.L., and Bowen, B.S. (2004) Geographic variation in Mexican jays (Aphelocoma ultramarina): local differentiation, polyphyly or hybridization? Molecular Ecology, 13 (9) 2721-2734

Brown Jay has pretty much disappeared from Texas, some time after early 2005 (when I saw 2 or 3 at Salineño).