In 1918, a group of professional crayfish fishermen working out of Port Stevens on the coast of New South Wales, Australia, stopped visiting their regular fishing grounds near Broughton Island for several days. This was an unusual decision, as these men worked those waters for a living, and refusing paid work carried a real financial cost.
David George Stead, a naturalist and the manager of the state’s trawling industry at the time, happened to be at Nelson’s Bay wharf while lobsters were being packed for the Sydney market. He asked the fishermen whether a recent southeast storm had damaged their pots. According to Stead’s later account in his 1963 book “Sharks and Rays of Australian Seas,” the men did not speak about the storm. Instead, they described encountering what they called one great big shark.
Stead recorded that the fishermen described an enormous shark that appeared repeatedly at their grounds and lifted pot after pot straight off the seafloor, crayfish and all, taking the pots, mooring lines, and contents. These were not small traps. Stead noted the pots measured about 3 feet 6 inches across and often held two to three dozen crayfish, each weighing several pounds. A trap of that size, loaded and anchored by a mooring line, was a substantial object.
He also recorded that the fishermen said the water appeared to boil over a large area as the animal swam past, and that they had seen its head directly, describing it as at least as long as the roof of the wharf shed. Stead noted these men were familiar with whales, which they regularly saw passing offshore, yet they insisted the animal was unmistakably a shark. When asked for size estimates, individual men gave figures ranging from the length of the wharf itself, about 115 feet, up to one man’s claim of at least 300 feet. Stead acknowledged these estimates were almost certainly exaggerated beyond what was physically plausible for any known shark species.
Stead was not a casual observer. He was a working naturalist, an ichthyologist, and a figure who later founded the Wildlife Preservation Society of Australia. According to his own account, he did not simply accept the fishermen’s story on the spot. He followed up directly, questioning the men closely alongside a local fisheries inspector named Payton. Stead described the fishermen as prosaic and stolid, not given to telling fish stories, and noted they were aware that Stead had heard every exaggerated fish story imaginable over the years, making it unlikely they would invent one for his benefit.
Despite the inflated size estimates, Stead reported that every man questioned agreed independently on the animal’s gigantic scale and, in particular, its distinctly ghostly whitish color. Inspector Payton agreed with Stead’s assessment that something genuinely enormous must have frightened hardened professional men into that state. That follow-up investigation, conducted by a fisheries official rather than a journalist, is why this account has continued to generate discussion among marine biologists and historians.
A separate report from American author and angler Zane Grey described a large unidentified shark seen in Pacific waters. Grey, who fished Australian and South Pacific waters during the 1920s and 1930s, described in his 1931 book “Tales of Tahitian Waters” an enormous shark sighted while sailing near Rangiroa in French Polynesia around 1927 or 1928. He described an animal with a square head, huge pectoral fins, and a length considerably exceeding his 35 to 40-foot boat. His account differed from the Port Stevens description in one notable way, describing the animal as green, yellow, and speckled with white spots, possibly barnacles, rather than the uniform ghostly white color the Port Stevens fishermen had described. This difference matters when evaluating both accounts, as researchers have noted the ghostly white coloration does not match the confirmed coloration of any living giant shark species, most of which display darker, mottled, or spotted patterns.
Some researchers have suggested a more mundane explanation for the 1918 incident. The fishermen’s pots, and possibly a boat, may have been damaged or destroyed by the same storm Stead originally asked about. The men may have invented a monster shark story to cover their financial losses. This kind of economic incentive is a plausible human motivation, particularly for working fishermen whose livelihoods depended on their equipment and reputation. Skeptics have also pointed to the wildly inconsistent size estimates as a warning sign, suggesting panic, poor visibility, or genuine misperception played a larger role than a single consistently sized animal. Fear and poor lighting conditions at sea are known to produce exaggerated, inconsistent reports even among honest witnesses. Neither of these explanations has ever been definitively proven, and no physical evidence from the 1918 incident survives.
Modern marine biology confirms that some real shark species grow considerably larger than most people realize. Whale sharks, the largest fish species alive today, have been confirmed reaching lengths of up to roughly 61 feet, but they feed primarily on plankton and small fish and do not attack large prey or equipment. Basking sharks, the second largest living fish species, are similarly docile filter feeders reaching lengths of around 26 to 33 feet. Great white sharks are aggressive predators capable of investigating and damaging fishing gear and grow to a confirmed maximum length of around 20 feet, far short of even the most conservative estimate given in 1918. No confirmed living shark species combines unusually large size with active aggressive feeding behavior directed specifically at anchored fishing gear.
Some online speculation has suggested the 1918 shark may have been a surviving population of Otodus megalodon, the enormous prehistoric shark whose fossil teeth are found on multiple continents. Paleontologists, however, have placed megalodon’s extinction at roughly 3.6 million years ago based on where its fossil teeth stop appearing in the sediment record. A 2023 study in the Proceedings of the National Academy of Sciences found that megalodon maintained an unusually warm body temperature, a trait requiring enormous amounts of food that likely became unsustainable once oceans cooled and its prey died out or migrated. Researcher Carl Shuker has also noted that fossilized megalodon teeth are generally black, gray, or brown rather than white, which does not match the ghostly white coloring described by the Port Stevens fishermen. No fossil evidence has ever been recovered near Port Stevens tying the 1918 account to that species, leaving the connection speculative.
Considerably more recent discoveries off the Australian coast have confirmed the presence of genuine giant animals that were previously undocumented. In July 2026, researchers from Curtin University, the Schmidt Ocean Institute, and the Western Australia Museum confirmed genetic evidence of a giant squid living in deep ocean canyons off Western Australia’s Ningaloo coast. Dr. Lisa Kirkendale described it as the first record of a giant squid detected off Western Australia’s coast using environmental DNA testing and the northernmost confirmed record of the species in the Eastern Indian Ocean. Giant squid rank among the largest invertebrates on the planet, growing between roughly 30 and 40 feet long and weighing up to 600 pounds. The research team deployed cameras and remotely operated vehicles into submarine canyons at depths exceeding 14,000 feet but never captured direct visual footage of the animal. The genetic material recovered from water samples proved conclusively that a real giant squid had been present in that area, even though it avoided every camera. Australian waters have produced physical giant squid specimens before, including a confirmed 500-pound giant squid that was pulled up dead in a trawler’s nets off the country’s southeastern coast.
In 2020, researchers aboard a Schmidt Ocean Institute research vessel documented an enormous siphonophore belonging to the genus Apolemia while exploring the Ningaloo Canyons, estimated at approximately 45 meters long when its full structure was measured. That length would make it among the longest animals ever recorded, longer than a blue whale. A siphonophore is technically a colony made up of many smaller genetically identical individual organisms called zooids, each specialized for a different function like feeding, swimming, or reproduction. Researchers have noted that sightings like this suggest these massive soft-bodied colonies may be more common in the deep ocean than previously expected.
Australia’s coastline borders an unusually large stretch of deep, largely unexplored ocean, including submarine canyons that drop to extreme depths just off otherwise well-known coastal regions. This geographic combination creates real opportunities for large, deep-dwelling animals to occasionally surface into or near shallower waters where fishing boats and casual observers might encounter them. Researchers involved in the recent giant squid and siphonophore discoveries have connected their findings to this same reality, noting that advances in deep sea exploration technology continue to turn up genuinely new information about animals living in Australian canyons that traditional fishing and casual observation alone could not have documented.
Marine biologists and historians revisiting the 1918 Port Stevens account today generally take a position between full belief and complete dismissal. The witness testimony came from multiple independent, experienced professional fishermen cross-examined directly by a credentialed naturalist and an official fisheries inspector, which carries real documented weight. At the same time, the size estimates were wildly inconsistent and physically implausible for any confirmed shark species, and the alternative explanation involving storm damage and an invented cover story remains plausible. No physical evidence, no recovered tooth, no photograph, and no confirmed carcass has ever surfaced connecting the incident to any specific species.
What has changed since 1918 is the volume of confirmed evidence showing that genuinely enormous, previously undocumented animals really do live in Australian coastal deep water. Evidence that did not exist for Stead or the fishermen he interviewed to draw on. The 1918 Port Stevens case remains unresolved, but modern Australian marine research continues to confirm that the deep water sitting just off the same coastline holds genuine, scientifically significant surprises that even the best equipment available today cannot always capture on camera.
