Albinism in Animals

Science class taught us that the traits of the parents get passed down to their offspring.  For example, two people who have genes for brown eyes will mostly likely have brown-eyed children.

A Leucistic American Goldfinch (photo: Gay Schroer)

But what happens when two perfectly normal parents produce an albino offspring?  Albinism is caused by a genetic mutation that prevents the development of melanin, the pigment that colors our eyes, skin, and hair.  That lack of pigment causes albino animals to appear entirely, or at least mostly, white, and have pale blue or pink eyes.  Some animals are naturally white, like Mute Swans for example, but only albinos will have the pale eyes.  Animals that depart from their normal coloration and have some white on their body, but not completely white, are leucistic.

In the wild, being albino can cause a variety of problems. The white coloration causes the animal to stand out, making it easier for potential predators to spot. However, the white coloration might also make the animal unrecognizable as a prey species.

Another issue caused by albinism is that members of the albino’s own species may reject it. Albino animals, especially birds, may not be able to find a mate because they lack the coloration and patterns necessary to catch the eye of the opposite sex.

A wild Albino Barred Owl (Photo: Kelly Bietsch)

Albinism also affects eyesight. Melanin helps in the development of the eye, and animals that lack melanin often have poor vision. An albino’s eyes are often more sensitive to light, less able to distinguish color, and less able to perceive depth. It is possible that an albino animal would have more trouble finding food or seeing danger, thus decreasing its chances of survival.

In the wild, albinism is not common. The frequency of albinism occurring varies from species to species, but generally albinism is more common in birds than in mammals. According to the Missouri Department of Conservation, albinism occurs in approximately one out of every 10,000 mammal births, while approximately one out of every 1,764 birds is albino. Although most, if not all, species can produce albinos, the only commonly albino species are those that are domesticated. Many people like to have albino pets, whether it be a cat, snake, or rat.

Kahn, WBS's albino Burmese Python (photo: JoHanna Burton)

At the World Bird Sanctuary, we do have a couple of albino animals. One of the most popular animals (depending on how you feel about snakes) is Kahn, our albino Burmese python. A normally pigmented Burmese python is patterned tan and dark brown, with dark eyes. Kahn is patterned white and pale yellow, and if that weren’t enough to convince you that he is albino, you could take a look at his pink eyes.

Kahn enjoying his pool on a hot summer day (photo: JoHanna Burton)

You can come to visit Kahn at World Bird Sanctuary's Nature Center, and on warm summer days you might just find him outside with a naturalist, enjoying a refreshing bath.

Submitted by JoHanna Burton, World Bird Sanctuary Naturalist

Leucistic Goldfinch

This seems to be my year for reporting sightings of white birds!

In December 2011 I belatedly reported a good friend’s sighting of a rare albino Barred Owl that occurred in the fall of 2010.

Rare albino Barred Owl - spotted in September 2010  

Then just recently World Bird Sanctuary Naturalist/Fundraiser, Catherine Redfern, took us along with her to Smithville Lake just North of Kansas City to view some of the Snowy Owls that have been spotted there as part of the unusual Snowy Owl irruption this year.  To read about this rare occurrence Click Here. 

One of the Snowy Owls seen at Smithville Lake in Missouri

To put the icing on the cake, just recently I was excited to see a most unusual bird at my thistle feeder—a leucistic Goldfinch! 

The leucistic Goldfinch who has been a fairly regular visitor to my feeder this winter

To my amazement I began seeing this unusual visitor on a fairly regular basis about two months ago.  However, until just a couple of weeks ago I had been unsuccessful in photographing this wary individual.  On the first few occasions when I saw it at the feeder it was gone by the time I grabbed my camera and changed my lens.  I had even resorted to leaving the camera, with long lens attached, sitting on my kitchen table.  (Martha Stewart would have been proud of my new creative table centerpiece.)  Of course the bird did not reappear until the camera was again safely stashed in my camera bag!   Finally, about three weeks ago, I was able to get a few photos—albeit through the two panes of glass in my kitchen window.

According to the Cornell Lab of Ornithology website, leucism is relatively unusual in birds, and from 2000-2006 Project FeederWatch participants reported fewer than 1,000 leucistic birds out of approximately 5.5 million birds reported each season!  I feel extremely fortunate to have seen this rarity.

Without the normal coloration it is difficult to differentiate between male and female

What is a leucistic bird you may ask—and how is it different from an albino bird?  Although there is some disagreement in the scientific community as to what constitutes the differences between these two mutations, all the experts seem to agree on one point—albinos have pink eyes and leucistic birds have dark eyes.  Albinism is a genetic mutation that prevents the production of melanin in the body, whereas leucism is a genetic mutation that prevents melanin from being deposited normally on feathers.

However, the above definition is a simplistic answer to a much more complicated question, since there are varying degrees of albinism and leucism.  To learn more about this fascinating subject click here. 

Don’t forget to keep your feeders filled this winter--you never know who might visit!

Submitted by Gay Schroer, World Bird Sanctuary Volunteer/Photographer