Giant shark

Lord of the Deep Illustration by William Rebsamen. Category Giant shark Proposed scientific names Other names Demonio negro ("black demon"), Lord of the Deep Country reported Pacific Ocean, Caribbean Sea First reported 1935 Prominent investigators • Michael Goss • Ben S. Roesch • Karl Shuker

Giant sharks are cryptids reported mainly from the South Pacific, as well as the North Pacific and the Caribbean Sea, considered a Coleman-Huyghe type of aquatic cryptid. They are associated either with oversized great white sharks (Carcharodon carcharias), or, more controversially, a surviving megalodon (Otodus megalodon), a giant prehistoric shark thought to have disappeared during the Pliocene. Karl Shuker describes megalodon's possible continued existence as "one of the most contentious, divisive subjects in the entire field of cryptozoology".

Description

Sightings of sharks included in this category are distinguished solely by their enormous size. Given lengths include between 20' and 60'; no less than 30'; 115' to 300'; longer than 40'; no less than 40' to 50'; 78'; 85' or longer; 40'; and 88'. These lengths represent an average of about 78', or more reliably 53', and about 40' is the most commonly-reported length.

Other characteristics vary between sightings. Colouration ranges from normal grey-and-white, to ghostly white or "whitish," to black, to yellowish. A huge, wide head and prominent pectoral fins are reported from sightings near Rangiroa.

Physical evidence

Teeth

A number of apparently-fresh megalodon teeth have been discovered, which have been used to support the argument that the shark still lives. In modern sources, these teeth are generally considered to have been reworked from older layers, although a 2014 study of megalodon teeth apparently included teeth dating to within the last 100,000 years.

The most famous of these teeth are a pair hauled up by the H.M.S. Challenger in 1875, from a red clay deposit south of Tahiti. In 1959, Russian scientist Wladimir Tschernezky attempted to date these teeth, based on the rate of formation of the manganese dioxide found in the formation, and concluded that one tooth was 24,000 years old, while the other was just 11,000 years old. Later scientists have mainly rejected Tschernezky's results, arguing that dating based on manganese dioxide is unreliable and produces dates based on several factors. In particular, Belayev and Glickman (1970) found that Managese dioxide buildup did not occur instantly once a tooth was discarded, and that Manganese dioxide dating produced wildly inaccurate results versus the ionium-thorium method. Tschernezky's teeth also had heavily degraded roots, a sign of older age. Coeval fossils from the area suggest a Mio-pliocene dating for Tschernezky's teeth, as they consist of ancestral white sharks and other Mio-pliocene species. Other "recent" O. Megalodon teeth are also found alongisde Mio-Pliocene genuses and use the Manganese dioxide dating method, and as such can probably be dismissed as erronaeous.

Attestations

The name "Lord of the Deep" is used by Polynesian fishermen who live along the coasts of New South Wales to refer to "a gigantic white shark, measuring about 100 ft in length," which they traditionally believe lives in those waters. The Polynesian form of this translated name is unrecorded.

Bruce A. Champagne has collected accounts of various miscellaneous large unknown sharks from marine biologists. These include a carcharinid shark almost 20' long from California's Bodega Bay, a "box head" lamnid shark from the South Pacific, and various other large sharks.

Sightings

Undated

Bernard Heuvelmans suggested that various enormous, hairy carcasses discovered in history could have been the putrefied carcasses of gigantic sharks like megalodon. According to Philippe Coudray, wounded whales have sometimes been discovered with injuries which imply the existence of an enormous shark. Fishermen in the Sea of Cortez, off the Baja California of Mexico, also claim to be familiar with a giant shark which they call "El Demonio Negro" (the Black Demon), described as between 20' and 60' long, with dark colouration and a massive tail.

In Shark! Unpredictable Killer of the Sea (1961), Thomas Helm claimed to have encountered a giant shark in the Caribbean, on an undisclosed date. As the shark passed underneath his 60' trawler, Helm was able to accurately gauge its length, which he concluded was "not an inch less than thirty feet," and its pectoral fins were visible in the water on both sides of the trawler. Neither Helm nor the other people on the boat could identify it, but it most closeley resembled a great white shark.

1918

The most famous alleged sighting of a gigantic shark is alleged to have occurred in 1918, near Port Stephens in New South Wales. Some fishermen there recounted to ichthyologist David G. Stead, in that year, that their heavy crayfish pots had been towed away by an enormous, ghostly-white shark. Upon seeing it, the men immediately weighed anchor and fled back to port, refusing to go out to sea again for some time.

“

In the year 1918 I recorded the sensation that had been caused among the "outside" crayfish men at Port Stephens, when, for several days, they refused to go to sea to their regular fishing grounds in the vicinity of Broughton Island. The men had been at work on the fishing grounds---which lie in deep water---when an immense shark of almost unbelievable proportions put in an appearance, lifting pot after pot containing many crayfishes, and taking, as the men said, "pots, mooring lines and all". These crayfish pots, it should be mentioned, were about 3 feet 6 inches in diameter and frequently contained from two to three dozen good-sized crayfish each weighing several pounds. The men were all unanimous that this shark was something the like of which they had never dreamed of.

”

The fishermen gave varying estimates of the shark's size, ranging from the length of the wharf on which they had been standing (115') to at least 300', a length regarded as a certain exaggeration, perhaps based on fear and shock. Stead and the Fisheries Inspector questioned the fishermen closely, and felt that they were genuine. "It must have been something really gigantic to put these experienced men into such a state of fear and panic".

1928

Western novelist and angler Zane Grey claimed in his book Tales of Tahitian Waters (1931) to have seen an immense shark while sailing off the French Polynesian island of Rangiroa in 1927 or 1928. Although an experienced angler of large fishes, Grey was unable to identify the shark, which was longer than his 35' to 40' boat, and had a square head, very large pectoral fins, and a greenish-yellow body speckled with white.

1927 or 1933

Zane Grey's son Loren also claimed to have seen a gigantic shark 100 miles northwest of Rangiroa, while aboard the S.S. Manganui with his father. The date of this encounter is sometimes given as 1933, but in 1994, Loren Grey stated in an interview that the sighting occurred two days after his father's. Loren Grey's shark, estimated by him to be no less than 40' to 50' long, was also described as yellowish with white flecks, and had a massive head some 10' to 12' across, and a large brown tail. Grey was convinced that the animal was not a whale shark.

“

At first I thought it was a whale, but when the great brown tail rose in the ship’s wake as the fish moved ponderously away from the liner, I knew immediately that it was a monstrous shark. The huge round head appeared to be at least 10 to 12 feet across if not more ... It was my belief that this huge, yellowish, barnacled creature must have been at least 40 or 50 feet long. He was not a whale shark: the whale shark has a distinctive white purplish green appearance with large brown spots and much narrower head. So what was he---perhaps a true prehistoric monster of the deep?

”

Much later, Loren Grey recounted his sighting to the Los Angeles Times in 1994:

“

[...] while on the boat we saw birds flying erratically over a yellow-colored patch of water. I thought it would have been a whale, but its tail stuck 10 feet out of the water [...] It was not a whale shark or a basking shark, it was brown like all the smaller ones in the area, which rarely get up to 10-12 feet long. I looked right down at him, and the head was as wide as this room. It had to be 50 feet long. [...] And not only did I see it, everyone on the boat saw it. And then Pa, who had been up on the deck, comes running down and said, ‘See, son, I told you; I’ll make you eat crow!'

”

1954

In 1954, a ship was allegedly attacked by an enormous shark in the southern seas off Adelaide, in South Australia. The bite mark left on the ship's hull measured 2 meters in diameter, and a number of teeth or teeth-marks were discovered, 10 centimeters long and 8 centimeters wide at the base. From these dimensions, the shark was estimated to have been 24 meters long.

~1960s

According to B. C. Cartmell, during the 1960s the captain and crew of an 85' ship sailing the outer edge of the Great Barrier Reef claimed privately to have seen an immense shark, as large as or larger than their boat.

“

... it moved slowly past their ship. Whitish in color, they were awed by its size. It was as long if not longer than their boat! Experienced men of the sea, they too were certain the creature was not a whale.

”

~1970s

Sailor Dave Brinks and his wife claimed to have encountered an enormous great white shark during the 1970s, while sailing a 40' boat some 100 miels west of Monterey Bay in California. The shark swam alongside their boat, allowing them to see that the animal was just as long as the vessel. The shark quickly veered off to the west, swimming underneath their boat, forcing it upwards, before disappearing.

1980

A shark estimated to be 27 meters long was supposedly observed off the Australian coast, in Queensland and New South Wales, several times in 1980.

Theories

The largest known predatory shark alive in the modern era is the great white (Carcharodon carcharias) (Source).

Both of the Grey sightings describe animals which resemble whale sharks (Rhincodon typus) (Source.)

A tiger shark (Galeocerdo cuvier) has also been suggested as a possible explanation for the Grey sighting.

Reconstructed skeleton of a megalodon at Calvert Marine Museum in Maryland. (Source).

A giant 20' shark ("Submarine") reported to live in the waters near False Bay, South Africa, was once considered a possible example of a megalodon, but was later established to be a very large great white shark (Carcharodon carcharias). The great white is the largest known predatory shark alive today. It has an average length of 11' to 13', but may grow to as long as 23' or 37'. The existence of larger specimens of the great white is considered plausible, and such animals could explain the Lord of the Deep, but some cryptozoologists have put forward the prehistoric giant shark, megalodon, as a possible explanation for these reports. Ben S. Roesch has extensively criticised the possibility that megalodon could still exist.

Both Roesch and George Eberhart regard the Greys' sharks as probable whale sharks (Rhincodon typus), which with their wide heads and white spots, fit the description given by both eyewitnesse, and Karl Shuker notes the resemblance of Zane Grey's shark to this fish. Zane Grey himself initially took the shark he saw for a whale shark, but concluded that the two animals were "in no way similar" beyond their sizes, and "figured out that the fish [...] was not a harmless whale-shark but one of the man-eating monsters of the South Pacific". Roesch believes that, if Zane Grey's shark was not a whale shark, it may have been a very large tiger shark (Galeocerdo cuvier), which have squared snouts. Loren Grey also insisted that his shark was not a whale shark, but Roesch argues that his description of a whale shark ("a distinctive white purplish green appearance with large brown spots and much narrower head") indicates that Grey did not really know what these animals looked like. Nevertheless, Roesch writes that a whale shark is not a perfect fit.

Roesch suggests that sightings such as the crayfish fishermen's and the Great Barrier Reef sighting are simply hoaxes or tall tales, and notes that the ghostly white colouration mentioned in both these sightings is inconsistent with the colouration of both pelagic and deep-sea animals. Furthermore, according to the Los Angeles Times, Zane Grey, despite being a "legendary" angler, "was known to exaggerate from time to time".

Due to the lack of remains beyond teeth and vertebrae, the appearance of megalodon in life is not known, and it may not have resembled a great white shark, as does the Lord of the Deep and most associated cryptids. It may have been more robust, with larger muscles and thicker jaws, as well as "a broader, blunter, and relatively more massive head". This is a possible point of similarity with the Greys' giant sharks, if they were not whale sharks.

The possible persistence of megalodon has mainly been criticised for ecological reasons, as the shark is believed to have lived in shallow waters, where it would likely be seen regularly in modern times. The reason for its apparent extinction is not known for certain, but it is believed to have been due to a combination of global cooling, a worldwide fall in sea levels, and the migrations of its cetacean prey into colder waters. Shuker suggests that megalodon may have been adaptable enough ("megalodon is now thought to have been sufficiently adaptable to have inhabited a wide range of environments, from shallow coastal waters and swampy coastal lagoons to sandy littorals and offshore deepwater abodes, exhibiting a transient lifestyle, and of near-cosmopolitan geographical distribution") to have survived such changes.

Shuker further speculates that megalodon might have become a deepwater species, preying on animals such as giant squids, which would explain both the apparent lack of fossil remains, and its ability to hide in the modern day. The palaeontological megalodon is not thought to have been a deepwater species, and it is considered unlikely that it could have adapted to such a specialised habitat rapidly enough to live there in the present. However, Shuker argues that, as the only fossil remains of megalodon on record are teeth and vertebrae, it is impossible to say what specialised adaptations it may or may not have had and it may already have been able to live in deep water. Philippe Coudray writes along similar lines, theorising that megalodon could evade detection by living mainly in deep water.

Roesch, writing in 1998, regarded the case for megalodon as closed for the time being, concluding that it had no basis in fact. Writing in 2017, Shuker regards megalodon's continued existence as "an unlikely prospect, but [...] certainly an inordinately interesting one," though he believes that there is certainly enough ocean, and enough whale species, to theoretically hide a population of megalodons, or a shark of similar size.

In popular culture

• Megalodon survival is famously the subject of the Discovery Channel mockumentary Megalodon: The Monster Shark Lives (2013), which was popular enough to generate the mistaken belief that theories of megalodon survival originated with the programme. In fact, its survival was being discussed long before, as early as the 1940s, originally based on fresh-looking teeth. However, the programme did cause widespread confusion by convincing viewiers that megalodon's survival was definite.
• A surviving megalodon is the subject of the science fiction action film The Meg (2018), which is an adaptation of the Steve Alten novel Meg: A Novel of Deep Terror (1997). The book has also been adapted into a graphic novel in 2019, and has spawned seven sequels.