Unique look part of 300 animals
Charlotte's Web-Spinning Tales
Albinism appears in approximately 300 animal species in North America. This is a rare inherited absence of pigmentation or coloration. It is speculated that factors other than genetic ones, such as age or diet, may cause this abnormality. In addition, fish eggs exposed to heavy metals, like copper or mercury, can produce albinos.
Initially, verification of albinism relies on pigmentation and coloration. For instance, the majority of mammals have just the melanin pigment, but many animals have pigments other than melanin. Some, like certain butterflies, have pigments and structural colors. Such diversity hinders interpretation.
Generally, defining traits are white hair or fur, skin, feathers, scales and cuticle. Yet, not all albinos are pure white. Eyes are commonly red or pink resulting from the lack of pigment in the iris, which exposes the blood vessels of the retina. However, blue or green eyes do surface.
Misleading are animals mistaken for albinos, such as those with leucism, a partial loss of pigmentation. This happens to many creatures — like tigers, hawks and fish. They emerge white, pale or patchy but usually have normal eyes. How about flamingos which appear white if they have insufficient red carotenoid pigments in their food?
In reptiles, birds and amphibians, albinism is more prevalent. Large snakes like diamondbacks and boas tend to be affected — often pinkish and yellowish.
The occurrence is one in 1,800 birds, often house swallows and American robins. In mammals, it is one in 10,000.
Unique are albino bottlenose dolphins. Only 15 have been reported since 1962. In 2007, a pink one appeared in a Louisiana lake — pink because blood vessels were exposed through blubber and unpigmented skin. The last sighting of an apparent true albino was in December 2014, in the Indian River, right here in Brevard County.
The pet industry thrives on breeding albinos, especially Norway rats (also named brown rats); moreover, they are esteemed laboratory rats. Other favorites are albino Burmese pythons, patterned white with yellow and orange. Often bred, but scarce, are blue-eyed leucistic Burmese pythons; though non-albinos, they are equally stunning with their white bodies void of markings. In 2013, a 13-foot albino Burmese python was captured in Hialeah. An escaped pet?
Captivity increases survival for albinos. In the wilds, life is challenged by such obstacles as exclusion from family, lack of camouflage, impaired hearing and vision, and sun sensitivity. Alligators might survive only 24 hours.
Perplexing are albino squirrels which seemingly survive as well as pigmented species.
Tame or wild, albinos intrigue. On a nature walk, a little scrutiny might reveal an albino land snail gliding by.