Humans are fascinated by sharks. And the larger the shark is, the tighter its grip on our collective imagination. So et's take a look at the biggest shark of them all: the Carcharocles megalodon.
C. megalodon is thought to have grown to approximately 60 feet long, and to have gone extinct around 2.6 million years ago. However, not everyone is convinced that megalodon is dead and gone. Some megalodon truthers think the massive shark is alive and well and living undiscovered in the Earth's oceans—and they often point to the sightings described below as evidence.
Even if you believe that megalodon is long extinct (in which case, you're in good hands; scientists everywhere agree with you!), the myth of the modern megalodon is still fascinating. If nothing else, these alleged megalodon sightings prove humans are fascinated by the ocean's mysterious depths. And in an ideal world, that fascination might lead to increased interest in conservation of actual extant sharks.
HMS Challenger Teeth
This first entry isn't a sighting, but a fossil find that's sometimes brought up and frequently misinterpreted in discussions of whether or not megalodon is still with us.
In 1875, the British ship HMS Challenger pulled up a pair of megalodon teeth from a seabed. In 1959, Dr. W. Tschernezky of London’s Queen Mary College attempted to date the teeth by studying the buildup of the manganese dioxide layer on each tooth. Through examining manganese dioxide deposition, Tschernezky determined the teeth were 11,000 and 24,000 years old, respectively. If correct, those findings would indicate that at the very least, megs may have gone extinct far later than previously thought.
However, manganese dioxide dating is often unreliable, particularly in dating shark teeth. As Ben S. Roesch writes in the 1998 Cryptozoology Review article "A Critical Evaluation of the Supposed Contemporary Existence of Carcharodon megalodon," shark teeth are more durable than typical fossil bones, and are able to withstand considerable erosion. This can make it challenging to determine how old the teeth actually are. Many researchers now think it likely that shark teeth once believed to be post-Pliocene megalodon teeth were instead older specimens that were somehow moved from their original, older sedimentary layer and deposited in a younger layer.
David Stead and the 'giant' fish
In his book Sharks and Rays of the Australian Seas, Australian naturalist David Stead shared an anecdote, which some believe describes a terrifying encounter with Meg herself.
According to Stead, in 1981 he spoke with several crayfish fishermen who were so terrified of a shark they saw in their fishing grounds off Broughton Island that they refused to return to the ground for days. They claimed to have seen a shark of unbelievable size surface in the deep water of the fishing grounds, taking the pots and mooring with it. Given that the crayfish pots were over three feet in diameter and loaded with heavy catch, that would be no small feat. Stead and the local Fisheries Inspector, a Mr. Paton, questioned the men, who all agreed to the shark's monstrous size—one claimed that its head alone was "at least as long as the roof on the wharf shed at Nelson's Bay." Many said it measured around 115 feet in length. Others said the water seemed to boil where it surfaced. All of them were confident that it was a shark rather than a whale, and that it was pale white in coloring. Given that the men they spoke to were all hardened fishermen accustomed to sharks, whales, and other sea creatures, the conversations they had with these frightened witnesses left quite an impression on Stead and Mr. Paton.
But even if the shark observed by the fishermen were as massive as described, several signs indicate that it couldn't have been mighty meg. As Roesch writes in his 1998 paper, if megalodon were alive in the modern world and surviving in the deep sea, it's unlikely he would be the white color described in the 1918 accounts. Most deep-sea sharks are dark, rather than white, although there is a general misconception that dark, deep-sea habitats result in lack of pigmentation.
An 'immense shark' off the Great Barrier Reef
In his 1978 book Let's Go Fossil Shark Tooth Hunting, author B.C. Cartmell describes an alleged incident that took place off the edge of Australia's Great Barrier Reef in the 1960s.
According to Cartmell, the sailors involved initially refused to speak of the incident because they feared teasing. But after time, they admitted that when their 85-foot ship was forced to weigh anchor for engine repairs, the captain and crew were shocked to see a gargantuan white shark swim slowly past their stuck ship. It rivaled the boat in size. All aboard agreed it was not a whale.
Was it the megster? Probably not—but whatever the sailors saw that day, it's proof that the ocean is a fascinating place.
The 'Black Demon' of Cortez
The Black Demon of Cortez is believed to be a massive, black shark seen off Mexico's Baja Coast. Some reports allege that the big boy may even be comparable in size to the ancient megalodon. In one alleged encounter, fisherman Eric Mack reported that the Black Demon rocked his boat, while its towering tail stuck five feet out of the water. Of course, if the 'Black Demon' is real, that doesn't mean it's a megalodon—it could easily be a plankton-eating whale shark or even a large great white with melanism.
The enormous black shark was the focus of an episode of the History channel cryptozoology TV show Monsterquest. However, the investigators failed to find any evidence of the fabled 'demon.'
Zane Grey and the 'man-eating monsters of the South Pacific'
Novelist and deep-sea angler Zane Grey claimed to have had an experience with a massive shark that some believe could have been a megalodon. In the novel Megalodon: Fact or Fiction?, Rick Emmer writes that Grey claimed to have seen "one of the man-eating monsters of the South Pacific," a shark much longer than his 30-40-foot boat. Apparently, the shark was "yellow and green ... (with a) square head, immense pectoral fins and a few white spots." In other words, not a mere "harmless white shark."
What does it all mean?
As fun as it is to imagine these stories are evidence that megalodon is still alive, that's just not the case. As Meghan Balk, a megalodon researcher at the University of New Mexico, told The Daily Beast: “there is no doubt in the scientific community that Megalodon is extinct.”
Balk explains that megalodons stayed close to the coast, so if they were still alive today, we'd know—it would be hard to miss a 50-plus-foot super predator roaming the shores! According to Balk, "most large sharks occur in the upper 500 meters of the water column, probably due to productivity. The deep is much too nutrient poor to support such a large animal."
In many ways, Shark Week is responsible for popularizing the myth that megalodon is still around. In 2014, Discovery aired the highly controversial Shark Week 'mockumentary' ''Megalodon: The Monster Shark Lives.'' The incredibly misleading program presented 'evidence' that megalodon was not only still alive, but also attacking humans and boats. Although a brief disclaimer at the end of "The Monster Shark Lives" explained that it was a work of fiction, many viewers were understandably fooled by the 'eyewitness accounts' and interviews with 'scientists.' The next year, Discovery aired a follow-up mockumentary called "Megalodon: The New Evidence," which only compounded the confusion.
Sadly, even if megalodon were discovered to be alive today, experts say it's likely humans would soon put them on the path to extinction again.
Conservationist, shark expert, and Shark Week critic David Shiffman wrote in 2014 that if megalodon were alive today, it would probably be hunted to extinction for its fins. He estimates that if hypothetical modern-day megalodon has 1.5 metric tons of fins, it could be sold for around $600,000, and make approximately 70,456 bowls of megalodon shark fin soup.
And, as Shiffman points out, "if the hypothetical overfishing of a species that has been extinct for millions of years has you as upset as it has me, you should learn more about the real overfishing of shark species that are still around… at least for now."