Past Featured Whales
White whales have been famous ever since Herman Melville published Moby Dick in the 1850's. Moby Dick was supposed to be an albino sperm whale. In reality, Moby Dick was based on a real whale named Mocha Dick who was famous in the 1820's and 1830's in the South Pacific. This whale was not white but supposedly "coffee" colored, but was otherwise similar to the animal that Melville described. True albino sperm whales have now been seen and even filmed several times; the PBS-TV series "Nature" aired dramatic underwater footage of a young albino sperm whale calf several years ago. In addition, one in every 100 southern right whales is born light colored, although they darken with age. We also know a totally white humpback whale that has been seen since the late 1980's off the coast of Australia.
Not all white animals are true albinos. Albinism indicates a true lack of pigment, so eyes also lack any color as well. However, there can also be animals that have pigment, but it does not show up well or is weaker than usual. This is likely the case with our young pilot whale, as reflected by the gray color on the back. We have also tracked a number of Atlantic white-sided dolphins that have unusually large white patches on their body, although there are parts of them that are normally pigmented.
The usual light/dark coloring pattern of whales and dolphins (and many fish species) is referred to as
counter-shading
, because the animals are lightly colored on their undersides and darkly colored on their topsides. As a result, when viewed from below in the upper water column, the light belly would tend to blend in with the daytime sky above, making them difficult to see. Conversely, when viewed from above, the dark back would tend to blend in with the dark waters below. Because this helps them blend into their background visually, it is thought that it helps them escape predators (killer whales and, possibly, sharks). We don't know if the white coloration on the whale leaves it more vulnerable to attack because it can be seen more easily, but our sighting record of other white animals indicates they can survive for long periods.
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