Shark or sea monster? The Canadian marine mystery that still intrigues experts 90 years on | Marine life

IIts head resembled that of a dog, its downturned nose resembled that of a camel, and at the end of its reptilian body was the tail of a horse. Witnesses say it was covered with a thin white film. When the remains of a strange creature were extracted from the stomach of a sperm whale, most of those present agreed: it was a sea monster – or at least something unknown living in the depths of Canada’s west coast.

Crews at the Haida Gwaii whaling station assembled a platform of wooden crates and laid out the 3-meter (10-foot) carcass, using a white sheet to display the curiosity that had baffled the veteran whalers.

A photo of the creature, called “Cadborosaurus” by locals, appeared on the front page of a local newspaper on October 31, 1937, adding to the growing rumor that a marine cryptid – a creature unknown to science – and sometimes measuring three times its length, was stalking the waters.

Samples of this mysterious discovery have long since disappeared and only a handful of black and white images remain.

John Kirk, president of the British Columbia Scientific Cryptozoology Club, is adamant the carcass belonged to an unknown species hidden at the edge of human understanding in the emerald depths of the Salish Sea. He cites first-hand accounts of the discovery, including an interview with a skinner who helped remove the carcass.

“The scientific world, of which we are a part, is always looking for excuses not to admit new animals into the catalog. And frankly, I find this notion absolutely far-fetched,” he says.

One of the few pieces of carcass sent for identification was shipped to a museum in Victoria, 400 nautical miles (740 km) southeast of Haida Gwaii. It was eliminated after the museum director – who is not a trained zoologist – suggested it came from a baleen whale fetus.

“We lost a massive discovery here because of misidentification,” says Kirk. “And I think it’s a horror story of how flippant scientists can sometimes be about this stuff.”

But nearly 90 years later, many scientists say the images simply show a decaying basking shark — a giant, ancient fish that once thrived off Vancouver Island before being culled to near local extinction. Today, the basking shark shares the fate of the cryptid: often misidentified and rarely, if ever, seen by veterans of the ocean.

Because sharks have no bones, the transition from a living creature to a carcass is a profound transformation. When basking sharks decompose, their enormous gill basket – the structure that best defines this heavy fish – collapses. What remains is a long neck-like structure and a small head. The breakdown of muscle fibers and cartilage can give the fins a hairy, feather-like appearance.

“With a long spinal cord and a small head at the end, it looks like a mythological sea serpent,” says Ben Speers-Roesch, professor of marine biology at the University of New Brunswick. “Unless you know what you’re looking at or are familiar with it, it’s not intuitive to know what this creature could have been.”

In 1977, the Japanese trawler Zuiyō Maru pulled a creature from the depths off the coast of New Zealand that looked like a long-lost dinosaur. The discovery sparked a wave of excitement from scientists who claimed it was an unknown species, until an analysis of amino acids in the muscle tissue suggested it was a basking shark.

Speers-Roesch says this is called the “pseudo-plesiosaur carcass” phenomenon, when decomposed basking sharks appear to have long necks, small heads and large paddles – all characteristics of a prehistoric plesiosaur.

He admits that the 1937 photo taken in Canada deviates from typical carcasses because of the way it was exposed.

“The mystery persists because it contains elements that are not as easily identifiable as a basking shark. It looks a little different in several ways,” he says, adding that on rare occasions young basking sharks have been found in the stomachs of sperm whales. “But a lot of the carcass captures what we know about basking sharks and how they decompose. Even if you’re well educated, you can really make bad interpretations of what you observe.”

With no surviving samples and only a handful of photographs, the question of what this mysterious creature was can never be definitively answered. But the real story, scientists say, is not so much the mystery of a species that might exist, but the tragic end of a species that did exist. Now, amid efforts to protect Pacific waters and remaining vulnerable species, a rare sighting of a basking shark in 2024 has reignited interest in the species and the long-forgotten campaign that eliminated it from coastal waters.

In 1955, the federal government developed a plan to kill sharks. His strategy relied on a large blade attached to the bow of a patrol vessel, dubbed a “razor-beaked shark slicer” by local media.

“As the basking sharks were feeding on the surface, crews could lower the blade and crush them,” says Scott Wallace, a former fisheries scientist who wrote the 2007 federal government report that determined the basking shark was endangered and largely extinct in British Columbia waters. “They just cut them in half.”

The sharks’ only crime was inadvertently wandering into the nets set by anglers to catch salmon.

“Everything that interacted with salmon or with salmon fishing was killed in an effort to think they could manage the ocean again,” says Wallace, co-author of the book Basking Sharks: The Slaughter of BC’s Gentle Giants.. “And it didn’t take long for basking sharks to be added to the ‘official nuisance list’ and become a target.”

At the same time, authorities were shooting seals and sea lions around fishing grounds and river mouths. In the early 1960s, the Canadian Department of Fisheries installed a .50-caliber machine gun on an island, a weapon typically used against armored vehicles and low-flying aircraft. Its sole purpose was to kill orcs. The high-powered cannon was never used, but the message was clear: the giants of the ocean were to be destroyed and disrespected.

The government estimates it killed at least 413 basking sharks with these boats over the next 14 years. At the same time, up to 1,500 sharks may have been killed by entanglement. There was also a brief attempt to create a commercial fishery for their liver oil, but experts say it’s unclear how many sharks were culled in that effort. In total, no less than 2,600 – or more than 90% of the population – were eradicated.

Now, federal law prohibits killing, harming or capturing a basking shark if it is found off the coast of British Columbia. The government has a formal recovery strategy and action plan, and sharks are protected by the strongest wildlife protection measures in Canadian law. But Canada’s Department of Fisheries also admits it could take 200 years for sharks to return to a healthy population.

“There are periods – often decades – during which they [basking sharks] they just disappear,” Wallace says. “And then all of a sudden, they come back. Maybe it’s because of ocean conditions – we really don’t know. But there is a chance, and it is slim, that they are still in the area, out of human sight.”

Although the tragic story of the basking shark’s demise is indisputable, the phenomenon of the “pseudo-plesiosaur carcass” is not enough to convince some that the mysterious creature in the 1930s photograph is anything identifiable.

“The carcass is definitely not a basking shark,” Kirk says. “And it’s not a reptile. Either way, it must be a mammal because it has hair and it doesn’t look like any of the orders of marine mammals found in these waters today.”

For Kirk and cryptozoologists, the prospect of something that eludes scientific acceptance is a powerful lure and underscores their relentless hunt.

In 2010, while walking his dog, Kirk said he encountered an unknown creature in the waters where British Columbia’s Fraser River flows into the Salish Sea. Its head was “pointed” and the neck stuck out of the water “like a stovepipe” with a hump curled behind it. The encounter was a “breathtaking experience” and left him stunned.

“But I can tell you this: in my almost four decades in the area, one thing I have never seen is a basking shark,” he says. “I don’t know if I ever will.”

Speers-Roesch understands the urge to look at a century-old photograph and believe that something unexplored still lurks in the ocean. But the connection between the human senses and the natural world is a space filled with errors. Under the right conditions, a carcass looks nothing like the living animal. When a dead raccoon washed up on a shore on Long Island, New York, word quickly spread that the bloated, hairless carcass was an unknown creature called the “Montauk Monster.”

“Humans will always be curious about the unknown,” says Speers-Roesch. “There are still deep mysteries and species in the ocean that we know very, very little about, and probably even species of relatively large animals that have yet to be discovered or described. But when you actually look at the creatures that are known to exist in the ocean, it’s even more spectacular and powerful.”