Great whites, the largest predatory sharks in the world with the most fatal attacks on humans, are tough to imagine as newborn babies. That is partially because no one has seen one in the wild, it seems, until now.
Wildlife filmmaker Carlos Gauna and UC Riverside biology doctoral student Phillip Sternes were scanning the waters for sharks on July 9, 2023, near Santa Barbara on California's central coast.
That day, something exciting appeared on the viewfinder of Gauna's drone camera.
It was a shark pup unlike any they'd ever seen.
Great whites, referred to only as white sharks by scientists, are gray on top and white on the bottom.
But this roughly 5-foot-long shark was pure white.
"We enlarged the images, put them in slow motion, and realized the white layer was being shed from the body as it was swimming," Sternes said.
"I believe it was a newborn white shark shedding its embryonic layer."
These observations are documented in a new paper in the Environmental Biology of Fishes journal.
The paper also details the significance of having seen a live newborn white shark.
Gauna is known online as The Malibu Artist. He has spent thousands of hours filming sharks around the world, and his videos of them swimming close to beachgoers have millions of views.
What he and Sternes observed could help solve the longstanding mystery of great white birthing habits.
"Where white sharks give birth is one of the holy grails of shark science. No one has ever been able to pinpoint where they are born, nor has anyone seen a newborn baby shark alive," Gauna said.
"There have been dead white sharks found inside deceased pregnant mothers. But nothing like this."
Though the paper authors acknowledge it is possible the white film the shark shed could have been a skin condition, the duo do not believe this to be the case.
"If that is what we saw, then that too is monumental because no such condition has ever been reported for these sharks," Gauna said.
For many reasons, the duo believes what they saw was in fact a newborn great white.
First, great white females give birth to live pups. While in utero, the embryonic sharks might feed on unfertilized eggs for protein.
The mothers offer additional nourishment to the growing shark pups with a 'milk' secreted in the uterus.
"I believe what we saw was the baby shedding the intrauterine milk," Sternes said.
A second reason is the presence of large, likely pregnant great whites in this location.
Source: ScienceDaily
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