As the drone ascended from the rugged cliffs of the Southern California coast, its camera lens poised to capture the secrets of the vast Pacific Ocean below, the unfolding video footage initially appeared serene and unassuming. Hovering over the azure expanse, the drone’s eagle-eyed view revealed nothing but endless waves rolling rhythmically towards the shore. Minutes passed and soon surfers came into view, gliding gracefully atop the wave’s crests. Soon, a playful pod of dolphins emerged, their sleek forms breaking the surface with effortless grace. And then, as if summoned by the ocean’s mystique, a peculiar sight materialized—a large great white shark (Carcharodon carcharias), moving erratically in the water before diving beyond the drone’s viewpoint. moments later... a small great white shark appeared.
A very small great white shark.
In this fleeting moment, the drone bore witness to something the shark science world has been chasing for decades.
The scene described above is similar to what Carlos Guana, a wildlife filmmaker, went through last July. “During one of my countless hours of filming white sharks I came across a very peculiar looking white shark. This small shark was literally white all over,” explains Gauna, also known as The Malibu Artist. “While Southern California is home to many white shark nurseries, this wasn’t technically in one. It was at a specific location that I’ve made some anecdotal observations over the years that were quickly becoming a trend. For the previous [three] years, a local aggregation of very large seemingly pregnant white sharks are visible for only a short period of time. I use the word ‘seemingly’ because the only way to confirm this, is by a means I don’t have access to. But based on the countless hours of observations I’ve made of sharks of all sizes, including pregnant ones, I deduced that some of these sharks were indeed pregnant.”
“It has been hypothesized by other researchers that white sharks are born in shallow, coastal waters ... [+]
But on this particular day, one large shark was visible. “It disappeared just beyond the visual depths following some erratic yet unexpected movements. Shortly thereafter, this small, completely white covered white shark appeared. It was unlike anything I’ve seen before.” The footage, published in the peer-reviewed journal Environmental Biology of Fishes, “was unlike anything we had ever seen before,” says study co-author Phillip Sternes, an organismal biologist at the University of California, Riverside. “It was exhilarating.” The team believes this could mark the first-ever observation of a newborn great white in the wild.
“The key is in the shape and size of the fins. Specifically the dorsal fin. It’s unmistakable that this is a very young white shark,” says Gauna. “The problem is, nobody has ever seen one so young before and this could very well be the youngest ever recorded alive. Notice the white substance. In our paper, we suggest this is a white uterine milk lining that has coated the shark. In the extended footage, the shark is visibly turning darker and shedding the layer.”
Great white sharks, notorious for their elusiveness, have puzzled scientists for decades. Their reproduction is of particular interest; unlike many other marine species, these sharks do not breed in captivity, making it difficult to study their reproductive behaviors up close. Due to the challenges associated with observing these apex predators in their natural habitat, no one has seen these sharks mate, let alone give birth. However, researchers have pieced together some insights into the reproductive biology of great white sharks through various observations and studies. Great whites are ovoviviparous (better known as ‘aplacental viviparity’), meaning that their embryos develop inside eggs within the mother’s body, and the mother gives birth to live young. Mating in great white sharks is believed to occur through a complex courtship ritual, although the details of this behavior remain largely undocumented. After mating, female great white sharks undergo a gestation period estimated to last around 12 months, although precise data on gestation duration is limited. Pregnant female great whites are believed to migrate to specific nursery areas, possibly in shallow coastal waters, to give birth to their pups.
While the birthing process itself remains largely unseen, researchers have occasionally encountered newborn great white sharks in the wild. But never this small. “Observations of free-swimming newborn white sharks are extremely rare,” Tobey Curtis, a shark scientist with the National Oceanic and Atmospheric Administration who was not involved in the research, told Science. “[It’s] nearly impossible to be in the exact right place at the exact right time to observe and document the moment of birth.” So, is this that possible moment of someone being in the right place at the right time? According to scientists who have analyzed the footage, the shark’s diminutive size and its rounded fins suggest that it was likely a newborn, possibly only a few hours old.
A small white shark covered with a light-hued film.
Yet, skepticism lingers. Gavin Naylor, director of the Florida Program for Shark Research, urges caution, noting the speculative nature of the finding. “White sharks typically have between 8 and 12 pups at a time, so where are all the others,” Naylor, who wasn’t involved in the study, told CNN. There also exists the possibility of alternative explanations for the shark’s appearance. The exact origins of the milky substance surrounding the shark remain debated, and Sternes has speculated that the unusual coloration may have been caused by a skin condition.
Still, the implications of this discovery reverberate throughout the scientific community. The importance of identifying breeding grounds for great whites is crucial for their conservation efforts and this discovery is a significant step toward unraveling the mysteries of great white shark reproduction.
“More work and observations will be needed, as the sample size of this observation is only one,” the team says. “Nevertheless, in either case, the use of the aerial drone has provided shark science with another interesting set of information.”
https://news.google.com/rss/articles/CBMib2h0dHBzOi8vd3d3LmZvcmJlcy5jb20vc2l0ZXMvbWVsaXNzYWNyaXN0aW5hbWFycXVlei8yMDI0LzAxLzI5L2Ryb25lLWZvb3RhZ2UtcmV2ZWFscy1uZXdib3JuLWdyZWF0LXdoaXRlLXNoYXJrL9IBc2h0dHBzOi8vd3d3LmZvcmJlcy5jb20vc2l0ZXMvbWVsaXNzYWNyaXN0aW5hbWFycXVlei8yMDI0LzAxLzI5L2Ryb25lLWZvb3RhZ2UtcmV2ZWFscy1uZXdib3JuLWdyZWF0LXdoaXRlLXNoYXJrL2FtcC8?oc=5
2024-01-30 03:43:37Z
CBMib2h0dHBzOi8vd3d3LmZvcmJlcy5jb20vc2l0ZXMvbWVsaXNzYWNyaXN0aW5hbWFycXVlei8yMDI0LzAxLzI5L2Ryb25lLWZvb3RhZ2UtcmV2ZWFscy1uZXdib3JuLWdyZWF0LXdoaXRlLXNoYXJrL9IBc2h0dHBzOi8vd3d3LmZvcmJlcy5jb20vc2l0ZXMvbWVsaXNzYWNyaXN0aW5hbWFycXVlei8yMDI0LzAxLzI5L2Ryb25lLWZvb3RhZ2UtcmV2ZWFscy1uZXdib3JuLWdyZWF0LXdoaXRlLXNoYXJrL2FtcC8
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