Introduction: Pink Bottlenose Dolphin Spotted in Louisiana:
A pink bottlenose dolphin, aptly called "pinky," was a hot news item after it was spotted in Calcasieu Lake, an inland saltwater estuary in Louisiana (News Video on Pink Dolphin). The light-skinned, red-eyed youngster was originally spotted in 2007, and has been in the news again this year. According to the Whale and Dolphin Conservation Society (WDCS), the pink coloration could be due to a "degree of pigmentation loss" or "the degree of blood vessels near the surface of the tissue."
So, how rare are albino cetaceans, and what causes this condition?
Albinism in Cetaceans:
Albinism has been documented in 20 cetacean species, including humpback whales, sperm whales, pilot whales, and bottlenose dolphins. White (not necessarily true albinos) killer whales and southern right whales have also been documented recently.
About Albinism and Leucism:
Albinism is inherited, and occurs when both parents carry the recessive gene for the condition and the offspring receives both of the genes. Albinism causes a lack of melanin, the chemical which causes pigmentation, in the body. Depending on the degree of albinism, the individual may have all or some of the following characteristics: white or light skin and hair, pink or red eye coloring and often impaired vision.
Some animals do have pigment, but it is not expressed well, and these animals are white or lighter-colored than usual, but not true albinos. These animals have dark eyes. This condition is called leucism, and occurs when pigment is expressed only in certain regions of the body.
This appears to be the case with a southern right whale calf sighted off Australia in August 2008. The calf, named Wilgi Manung (Aboriginal for 'white whale,') is thought to be one of only 10 in the world, according to the Daily Mail Online.
In March 2008, a white killer whale was sighted by NOAA researchers aboard the Oscar Dyson off Alaska's Aleutian islands, although it is not known if this whale is a true albino.
The most famous white whale, other than the fictional Moby Dick, is Migaloo, an all-white humpback male that has been seen many times off Australia since 1991. He is apparently the only documented all-white humpback in the world, and it has not been confirmed that he is a true albino.
Challenges for Albino Marine Life:
While the animals described above appear healthy, albino or otherwise uniquely-colored animals can be subject to increased risk in the wild. Their light coloration may cause increased risk for skin problems or skin cancer, they will have less camouflage from predators, and they will stand out from others in their species and thus may be less likely to integrate socially or find a mate.
Those living close to shore like "pinky" the dolphin will be subjected to additional attention and disturbance from humans, causing increased stress, increasing the potential for vessel strikes, and effects on the animal's feeding and reproduction.
The Rarity of Albinism:
It has been difficult to find data on the numbers of albino cetaceans, other than to find out that they are relatively rare. After all, when one is spotted, it is a big news item! Of the species described here, the individuals reported were listed as the only animal or one of just a handful that had been described for that species. So if you ever do get to see an albino whale, consider yourself lucky (and send me a photo!).
- Kraynak, Cheryl. 2009. "Rare Albino and White Animals". (Online) Suite101.com. Accessed April 4, 2009 - no longer active as of 4/1/13.
- McLean, Sheela. 2008. "Rare White Killer Whale Spotted in Alaskan Waters from NOAA Ship Oscar Dyson" (Online) NOAA. Accessed April 4, 2009.
- NOAA - "Albino Dolphin in Northern Gulf of Mexico". (Online) NOAA. Accessed April 4, 2009.
- Rappleye, Christine. 2007. "Albino Dolphin Spied Around Calcasieu Lake" (Online). Beaumont Enterprise. Accessed April 4, 2009.