"ALBINO" YELLOW TANG
Zebrasoma flavescens
   Several people have emailed me photos of Yellow Tangs with white patches wondering what caused them. I have even seen a few of these fish myself. At first I thought the condition represented partial albinism of some sort, presumably caused by a genetic variation. In support of this, Dr. John E. Randall writes:

"Occasional individuals of species of Acanthurus, Ctenochaetus, Zebrasoma, and Paracanthurus exhibit bizarre color patterns that are probably the result of mutation or breeding by a mutant back to the normal color form. ... One common color variant is a xanthic phase, but the yellow is generally blotched with dark brown. Another is an albino form, but again rarely entirely white. ... Albino Zebrasoma flavescens have been seen in Hawaii but not with any dark pigment." (Surgeonfishes of the World, p. 17)

However, the remarkable series of photos below taken off Maui by Victoria Martocci clearly shows that the white patches on one Yellow Tang grew larger over a period of years, eventually covering the entire fish. This seems to indicate that the white patches might be caused by a disease rather than by genetic mutation, at least in some cases. As usual, "More research is needed."

Victoria writes: "Here's the fish we've been watching for years. It has ALWAYS been seen in the same 10 sq ft area of reef... Every Time!"