House Finch, probably female with some form of albinism.

Wow! I am so grateful you posted this thanks.

WOWZER! Great find and a spectacular close-up profile of oddity. TFS GWeals!

Thanks for posting this photo of this finch rarity! The dark eyes tell you right away that it's not an albino. It appears to be leucistic. I've seen many, many house finches from coast to coast but never a leucistic one like this so it appears that this condition is very uncommon among this species.

pbgrebe said:

Thanks for posting this photo of this finch rarity! The dark eyes tell you right away that it's not an albino. It appears to be leucistic. I've seen many, many house finches from coast to coast but never a leucistic one like this so it appears that this condition is very uncommon among this species.

Click to expand...

Thanks for the comment. First, I'm certainly not an expert in identifying these types of conditions (far from it) but there are two Facebook groups that seem to specialize in this. One is "Studying Color Mutations in Wild Birds" and the other is "Understanding and Identifying Color Mutations in Wild Birds & Other Animals." This photo was posted in both. Initially many agreed with your assessment of leucistic. Later responses were much more detailed going into nuances that I didn't understand. There seemed to be an agreement among this second group that this is OCA4/SLC45A2 Albinism. I have no idea what the coding means but OCA3/TYRP1 was a close second. The dark eyes were explained by the statement that most forms of albinism have pigmented eyes and that only type OCA1A are generally pure red while the others range from blue to brown. I can't comment on the accuracy of any of the above but am simply repeating what this second group of "experts" has to say.

A great portrait of this interesting finch.

GWeals said:

The dark eyes were explained by the statement that most forms of albinism have pigmented eyes

Click to expand...

There seems to be an issue with semantics here. “Albino” is one of those terms that have come to acquire multiple meanings and usages. There are basically two interpretations of the term: a popularized (or more common, classic) one, and one that is scientifically/medically based. The more conventional, popularized definition of the term is by far the most commonly used. It defines albino animals as being those which are afflicted by “full” albinism—that is, those which possess a genetic condition that renders them incapable of all or nearly all melanin production. Thus, by definition here, all albino animals have pink, red or pale (unpigmented) eyes. It’s because this is the most common definition among the populace that I used it in my previous post. And it’s probably for this reason that it’s even common for scientifically based entities to defer to this definition in communications with the general public (for example, as in these short articles posted on the Cornel Bird Lab website ( Albinism and Leucism - FeederWatch) and The British Trust for Ornithology website (Leucism & albinism ). The other definition is poorly known outside of the relevant professional circles. Besides those with “full” albinism it also includes animals with “partial” and “alternate” forms of albinism.

Regardless, you can’t reach beyond the available empirical evidence for the actual cause of this bird’s physical appearance. The only empirical evidence here is that of the bird’s phenotypic aspects, that is, the physical, observable expression of its genes. Its physical features are consistent with both leucism and some alternate forms of albinism. Therefore, in order to determine which of these is the actual cause, an appropriate sample from this bird from which a genetic analysis can be conducted will be required. Since this currently is lacking, the only thing that can be stated with certainty is that because it has pigmented rather than pink or red eyes, it’s not a “full” or what many would call, a “true” albino. Without a genetic analysis, anything else is just speculative. Though, from a speculative perspective some studies (for example: How rare are leucistic and albino birds? - Avian Report ) have reported that, though both are rare, leucism is more common than albinism—which, purely probability-wise, would suggest that the odds are greater that this finch is leucistic (though, as noted above, a serious cautionary consideration re. the veracity of the findings of the studies noted in the linked article is that they are not based on genetic analyses of the observed birds so there is no verification that all of the birds listed as leucistic actually are and don’t also include birds which have an alternate form of albinism). Anyway, no matter what the cause, this finch is a special, rare individual.