Tag Archives: albino crow

How to troll a corvid lover

In general, I find that crow people are lovely, and easy to get along with folk.  There are, however, two widely shared images that have proven themselves an effective trigger to turn an otherwise gentle corvid lover into a foaming at the mouth fact checker.  I say that as someone who has found themselves on the foaming end of that equation over some social media perpetuated misinformation on many occasions.  In the wealth of silly nonsense posts  a person could manufacture on corvids, why these are the two images that have become so ubiquitous on social media is a mystery to me.  Maybe it’s because people genuinely enjoy the narratives they offer, or have no reason to be suspicious of the images because they’re just beginning to learn about crow biology.   Or maybe some people know exactly what they’re doing and are just trolling to, ahem, ruffle a few feathers.

Either way, consider the following two images debunked.  So rest easy fellow fact checkers, until of course you see them posted again.  Probably tomorrow.

Myth: The infamous “baby crow

These are not baby crows.

These are not baby crows.

I blame this one on BuzzFeed.  In what was trying to be a cool post on crows, but really turned out to be just riddled with terrible photo choices, they start off with one of these pictures as evidence for how cute baby crows are (despite photos of very obviously different looking actual baby crow further down the in the same post!).  Since BuzzFeed ranks one of the more trafficked sites on the internet, searching “baby crow” brings up the photo attached to the story.

Fact: Those cute fluffy babies are actually a variety of baby rails, including a corncrake.  Notice how feathery and soft they look, like a baby duck or chicken?  That’s because there are basically two strategies for how young are born.   They can be altricial, which means you’re born naked and blind (i.e helpless) or precocial, which means you’re born fully feathered or furred and are ready to go from day one.

Actual baby crow

Actual baby crow

Fun fact, most birds that are ground-nesters, so game birds, waterbirds, etc., are born feathered and adorable.  Whereas most birds born in arboreal nests are little naked jelly beans.  Crows, fall into the latter category as anyone who studies crows, rehabs crows, or curiously peeked into a crow nest can attest to.

 Myth: White ravens are cannibalized and are social pariahs

poor raven

I have no hypothesis as to where this came from or how it generated such momentum on social media, other than that it’s dramatic and offers a kind of ‘misery loves company’ on a crumby day.

Fact:  Leucism, which is what this is, is pretty common in crows and ravens (check out this post if you want to learn more about the causes).  Not to this degree, of course, but even a complete leucistic like this are not unheard of.  Although life is certainly a bit harder for them (they’re a little more conspicuous, leucism is often nested in other health problems, etc.) the suggestion that they’re eaten by their mothers is nonsense.  They are however, generally subordinate to regularly colored ravens which is maybe the kernel of truth that this originates from.


Filed under Crow curiosities, Crow life history, Crows and humans

Crow curiosities: what causes white feathers?

ZB in flight.  Photo c/o Sarah Ramirez

ZB in flight. Photo c/o Sarah Ramirez

At a recent field site in Bellevue, one of my regular visitors was the most fantastically leucistic crow I had ever seen.  Naturally, I dubbed him or her “ZB” for Zebra Bird.  One or two white feathers is pretty common but this was something far more spectacular.  Something that, to the naive observer, may look like a whole different species of bird.  In response, I thought it might be helpful to talk about how and why crows have white feathers or other kinds of color aberrations.  First off, let’s put some definitions on the table since there are a few terms that often get mixed up, or have different definitions depending on your source.  The following definitions are based on those provided by Guay et al. 2012.

Albinism results from a complete lack of melanin in both the feathers and all the soft body tissues.  This causes red eyes and pink legs, making it very easy to spot.  Albinism is often associated with poor vision and hyper-activity which quickly removes it from the general population and why, when it is spotted, it’s usually only in young or captive birds.

A complete leucistic crow.  What makes it leucistic and not albino?  The colored irises.

Albino crow spotted in Franklin Park, Seattle*

Leucism is a complete lack of melanin in all or part of the plumage, but not necessarily the soft tissues.  It is sometimes referred to as ‘partial albanism’ but if you’re familiar with the definition of albanism (which hopefully you are now!) you know the term ‘partial albinism’ is oxymoronic.  Leusistic birds can have one or multiple white feathers, as is the case with my friend in Bellevue, or be completely white but with regularly colored eyes.  Their feet and bills may or may not appear pink like that of an albino bird’s.

Schizochrosim is a lack of a particular pigment.  So a bird lacking the phaeomelanin (brown) pigment, for example, would appear grey.

Melanism is exceptionally high deposits of melanin that make the animal appear darker overall.

Carotenism is a change in the amount, distribution or composition of caroteniod (red, yellow, orange) pigments.

Dilution is, as the name suggests, a muting of colors across all or part of a bird’s plumage.

How do these color abnormalities arise?  There are a couple of different pathways including genetics, diet and injury/disease.


Albinism is genetic, specifically, it’s linked to a recessive autosomal gene.  If you’re reading this and thinking “autosomal recesisve…what?” remember that humans have 23 pairs of chromosomes. Twenty two of them are autosomal and the last pair are sex chromosomes (you’re either XX or XY, sound familiar?).  Recessive means you need two copies of the gene to express the trait.  What this mutation does is cause an absence of the enzyme tyrosinase, which is used by the body to create some of the colored pigments. Because albinism is heritable, it can be bred into an artificial population by a skilled breeder, which is why you may see things like white tigers and lions in the entertainment business.  Despite their dramatic color variation from their peers, they are not distinct species-an idea I occasionally see being perpetuated on social media.  Genetics also plays a role in leucism, though it’s often only part of a more complicated mechanism.

A leucistic dark-eyed junco spotted at my feeder.

A leucistic dark-eyed junco spotted at my feeder.


Diets low in protein may also contribute to leucism, as the amino acid lysine has been correlated with increased white feathers.  This is supported by the observation that urban birds (who presumably have a diet lower in meat and protein) typically have more color aberrations than their rural or forested peers.  Carotenism, on the other hand, is very strongly influenced by diet, since animals cannot produce this color on their own.  A very familiar example of this is seeing the white young of flamingos who, in this early stage of life, have not yet had enough time to begin producing mass quantities of their pink pigments.


Lastly, age and injury may also contribute to feathers which fail to correctly pigment though this is poorly understood.  Somatic genetic mutation (i.e mutations that occur after conception) are associated with increased age, and indeed, older crows are more often seen with white feathers.  Avian Pox is known to play a role in carotenism though not much is understood about this.

ZB's eye catching leucism in fligh

ZB’s eye catching leucism in flight.  Photo c/o Sarah Ramirez

*Updates* a previous version of this post contained a typo stating that humans have 24 pairs of chromosomes.
A previous version stated incorrectly that a complete leucitic juvenile could be identified by its correctly colored iris.  Since blue pigments occur irrelevant of melanin, this is not the case.

Lit cited

Guay, P.J., Potvin, D.A., and Robinson, R.W. 2012. Abberations in plumage coloration in birds. Australian Field Ornithology 29 23-30.


Filed under Crow curiosities, Crow life history