Recreational divers recently stumbled upon a nurse shark with an extremely rare skin condition.
Nurse sharks normally feature a brown coloration over their entire body. However, earlier this year, recreational divers in Utila, Honduras came across one particular nurse shark with what’s known as piebaldism.
Piebaldism is a rare skin condition that results in a partial loss of body pigmentation, with the eyes remaining in their regular coloration. The unique coloring made this nurse shark easily identifiable, and the divers saw it on two different dives in two different locations.
The finding was recently published in a new study, “Observations of hypomelanosis in the nurse shark Ginglymostoma cirratum,” in the Journal of Fish Biology, led by researchers at Beneath The Waves (BTW). Working with members of the Caribbean Shark Coalition, the team at BTW saw this reported finding as an opportunity to emphasize the value of citizen science for shark and ray conservation.
“The diverse, non-traditional author list of this publication demonstrates that science can and should be made accessible to those beyond the scientific community in order to add to the scientific database of sharks, marine life, and marine habitats.”
In nature, if an animal relies on camouflage to hunt or avoid predation, unusual skin conditions could affect its ability to do this successfully, ultimately impacting its chance of survival. With the rarity of these conditions in sharks, little is known about their effects.
Piebaldism is part of a larger suite of pigmentation deficiencies called hypomelanosis. This includes albinism, which results in a complete loss of pigmentation in the skin and iris, and leucism which causes total or partial loss of body pigment and a blue coloration to the iris and body.
Hypomelanosis is incredibly rare in the animal kingdom, particularly in sharks, skates, and rays. Only about 5% of these species have been documented with these conditions, one being a tawny nurse shark with albinism, and another being a nurse shark with leucism. This year’s sighting of a shark with piebaldism was the first ever.
(Featured Image credit: Ellie Hopgood)