If ever there was a poster child for human-caused extinction, it was the Dodo. This odd-looking flightless bird, native to the remote island of Mauritius in the Indian Ocean, was first encountered by Dutch sailors in 1598. Barely six decades later, the Dodo was all but extinct, wiped out by hungry sailors and invasive species like rats and pigs brought along. Indeed, so swift was the Dodo’s demise that for more than a hundred years many scientists refused to believe the bird had ever existed at all. But when it comes to modern extinctions, few can compare in sheer brutal swiftness to that of a large, docile marine mammal that once plied the cold northern waters of the Bering Strait. Discovered in 1741, the gentle giant was almost immediately hunted to oblivion. This is the tragic story of Steller’s Sea Cow.

The discovery of Steller’s Sea Cow is almost as dramatic as the creature’s ultimate demise. In 1741, Russian Tsar Peter the Great commissioned an expedition to explore and map Russia’s remote Pacific coast, declaring that “Everything shall be discovered that has not yet been discovered.” On June 4 of that year, two ships, the St. Peter and the St. Paul, set sail from the Kamchatka Peninsula, commanded by captains Vitus Bering and Aleksey Chirikov. Bering had already commanded a 1728 expedition which confirmed that Europe and North America were not connected by a land bridge. The strait separating the two continents still bears his name to this day. Also aboard the St. Peter was German professor of medicine and botany Georg Wilhelm Steller, substituted at the last moment when the ship’s original doctor suddenly fell ill.

A few days into the voyage, a violent storm separated the two ships. Captain Chirikov carried on independently, discovering several of the Aleutian Islands in the process. Meanwhile, Bering explored and mapped the coast of Alaska. But foul weather frequently blew the St. Peter off course, and by September 1741 the ship’s supply of fresh fruits and vegetables had been exhausted. With nearly half of his 77-man crew dead or dying of scurvy and other diseases, Bering set course for home. However, in early November a storm wrecked the St. Peter off what is now known as Bering’s island in the Commander Archipelago, leaving Bering and his crew marooned. Bering, himself feverishly ill, died a month later on December 8. This left Georg Steller, the only member of the expedition in good health, to tend to the rest of the crew. While exploring the island, Steller collected various birds, seals, and other animals and fed them to his comrades, who soon recovered their health.

While waiting for the weather to improve, the crew also began to explore the island, and before long they began returning to camp claiming to have spotted mermaids swimming in the shallows around the coast. At first Steller dismissed these reports, until on May 21, 1742, he caught his first glimpse of these so-called “mermaids.” Fever and long, lonely months at sea must really have played tricks on the crew’s imaginations, for the creature Steller described was about as far from the traditional image of a buxom mermaid as it is possible to get:

“It is 28 to 35 feet long, and 22 feet thick about the region of the navel, where they are the thickest. To the navel this animal resembles a seal species, from there on to the tail, a fish…in the mouth it has on each side in place of teeth two wide, longish, flat, loose bones, of which one is fastened above the palate, the other to the inside of the lower jaw….The lips are provided with many strong bristles….The eyes of the animal in spite of its size are not larger than sheeps’ eyes and are without eyelids….They are occupied with nothing else but their food.”

Steller recognized the creature as a sirenian, and described it as communal in nature, travelling in large family groups and subsisting mainly on seaweed. He also gave it the scientific name Hydrodamalis stelleri – Steller’s Sea Cow. Today, Steller’s Sea Cow, re-designated Hydrodamalis gigas, is widely regarded as the largest sirenian ever to have lived, growing three times larger than its closest sirenian relatives, the dugong and the manatee. This enormous size was likely an adaptation to the cold climate, reducing the loss of body heat by increasing the animal’s volume relative to its surface area.

Unfortunately, however, the crew of the St. Peter soon made a key discovery that would doom these newly-discovered creatures to oblivion: they were delicious. A single cow yielded more than 3,000 kilos of meat, tender and flavourful like prime beef. Furthermore, unlike most sirenians the Sea Cow had a layer of blubber up to 10 centimetres thick – an adaptation to the frigid waters of the Bering Strait. This the crew rendered the fat into oil and drank it like water, describing its taste as vaguely reminiscent of almonds. Just two Sea Cows were enough to sustain the crew until August 1742, when they finished building a new ship from the wrecked remains of the St. Peter and sailed to Kamchatka. Of the 78 men who set sail in June 1741, 46 returned home.

Yet despite these hardships, the expedition was considered a success. Not only had Bering mapped large sections of the Alaskan coast, but Georg Steller had discovered numerous animals previously unknown to science, including Steller’s Eider, Steller’s Jay, Steller’s Sea Eagle, Steller’s Sea Lion, and – of course – Steller’s Sea Cow. Steller published his discoveries in a 1751 book titled De Bestis Marinis – “On the Sea Beasts” – which established him as one of the foremost naturalists of his age. Unfortunately, this recognition came posthumously, as Steller had died six years earlier at the age of 37 – unaware that he was both the first and last scientist to study the Sea Cow and was indirectly responsible for its ultimate demise.

It should be noted here that it was not the Sea Cow which sent hunters in droves to the Commander Islands, but rather the abundance of sea otters and their valuable pelts – of which Russia was a major trader. The Sea Cow was an incidental victim of this trade, furnishing an abundant and easily obtainable source of meat for otter hunting parties. Tragically, the Sea Cow’s communal nature proved its undoing. When one animal was harpooned, instead of fleeing, the rest of the herd gathered protectively around it, exposing themselves to further slaughter. The animal’s thick, buoyant blubber also made diving difficult, making them even more vulnerable near the surface where they usually resided. Meanwhile, the mass slaughter of sea otters led to an explosion in the population of sea urchins, which in turn decimated the stands of kelp around the island – the Sea Cow’s main food source. By 1755, the population of Sea Cows had declined so dramatically that a Russian geologist, having witnessed the slaughter during a copper prospecting expedition, sent a petition to the Russian government calling for the animal to be protected before it disappeared entirely. But his pleas were ignored, and in little more than a decade Steller’s Sea Cow was extinct, with the last sighting taking place in 1768. And while a Russian whaling ship claimed to have spotted a pair off Bering’s Island in 1962, this has never been confirmed.

From discovery to extinction, Steller’s Sea Cow lasted a mere 26 years. So swift was their demise that Georg Steller’s writings remain the only scientific description of the Sea Cow in the wild. No pelts or other soft tissue of the animal survive, though several skeletons are preserved in museums. Based on fossils discovered in California, Russia, and Japan, palaeontologists believe that Steller’s Sea Cow and its relatives, the Cuesta and Takikawa Sea Cow, once ranged across the North Pacific before climatic changes around 400,000 years ago caused a severe population bottleneck and restricted the last remaining communities to the Commander Islands. Indeed, genetic analysis of Sea Cow bones indicates that this population was highly inbred and likely already headed towards extinction. But even these massive natural forces could not compete with human action, which wiped out the Sea Cow in the blink of a geological eye. This disappearance – both gradual and sudden – may have impacted the ecology of the Pacific Ocean in significant ways. According to a 2022 study led by Dr. Peter Roopnarine of the California Academy of Sciences, the grazing of Sea Cows on the upper canopies of kelp forests likely allowed more sunlight to reach the ocean floor, allowing for a greater diversity of other seaweeds and algae. This, in turn, likely provided sea urchins and other animals with alternative sources of food, preventing the unsustainable consumption that plagues many kelp forests today. In other words, Steller’s Sea Cows may well have been a key part of the North Pacific ecosystem, whose disappearance had widespread impacts that we are only just beginning to understand. The tragic story of Steller’s Sea Cow thus stands as a poignant reminder of the fragility of the natural world and the often unpredictable dangers of its unchecked exploitation.

Bonus Facts:

Any video covering rapid extinction would be lacking without at least a brief mention of the insane tale of the passenger pigeon. The passenger pigeon once dominated the North American skies. It has been estimated that when Europeans first arrived to this continent late in the 15th century, there were three to five billion passenger pigeons already here. Legends abound about how these birds used to black out the sky when they moved en masse. John James Audubon, the famed naturalist and ornithologist, once said he saw a flock create a full “solar eclipse” for three days as it passed. While this is *probably* a bit of an exaggeration, accounts from towns across North America, like Columbus, Ohio and Fort Mississauga, Ontario, made it seem like a mass of passing passenger pigeons was something out of the Bible, even apocalyptic in nature. In fact, it’s estimated that the largest flocks of passenger pigeons were second only to the Rocky Mountain locusts in group size. For reference, the Rocky Mountain locusts could potentially swarm an area the size of California, with an estimated 12.5 trillion locusts in the largest such swarm ever recorded.

As for the passenger pigeon, when the birds nested, they formed colonies that were extraordinary in size. In 1871, a colony in central Wisconsin was recorded to have occupied 850 square miles, a little larger in size than the entire country of Georgia. In 1866, a passing flock of passenger pigeons was estimated to contain 3.5 billion of the birds, with the width of the flock about 1.5 miles and the length about 300 miles. Needless to say, if you were traveling under the flying column, an umbrella of some sort probably would have been a good idea.

So, what happened to these birds? How, in such a short time, could the passenger pigeon go from being more numerous than all other North American birds combined to extinct? Well, humans gonna human.

According to a hunting journal in 1913, the passenger pigeons were known to be “the gypsies of the birdom.” They traveled en masse to wherever they could find food and nesting habitats. They were known to travel up to eighty miles daily from their roost in search of food. And they ate… a lot. They had fondness for soft fruits like blueberries, strawberries, and figs. They also ate acorns and chestnuts. Henry David Thoreau once wrote, “It is a wonder how pigeons can swallow acorns whole, but they do.”

The plentiful chestnut, maple, oak, and pine forests of North America not only provided food to the passenger pigeon, but a home and a place to nest (or roost).

Those trees also provided ample firewood to humans. By the 18th and 19th centuries, the human population on the continent was exploding — from under four million in 1790 to seventy-six million by 1900. As human numbers grew, land was needed to accommodate. Unfortunately, this was the same land the passenger pigeons occupied.

But deforestation was only a contributing factor in the extinction of the passenger pigeon. The main reason they went from billions to zero in about a half century was because they were just so darn tasty, or at the very least, abundant and easy to kill.

When the first humans started showing up fifteen thousand years ago in the northern hemisphere, they immediately began including passenger pigeons in their diet. When Europeans began settling, they quickly figured out that passenger pigeons were a cheap source of food. By the mid 19th century, professional pigeon trapping was a major industry and massive punt guns were event invented to help the process, able to kill upwards of hundreds of birds in a single shot. By 1855, the number of passenger pigeons were noticeably declining, though the flocks were still massive as noted above, so very little was done about it.

In 1857, a bill was presented to the Ohio State legislature, but was quickly dismissed. A report was filed that read,

The passenger pigeon needs no protection. Wonderfully prolific, having the vast forests of the North as its breeding grounds, traveling hundreds of miles in search of food, it is here today and elsewhere tomorrow.

A huge nesting area was found in Petoskey, Michigan in 1878. Trappers flocked there and, according to the Smithsonian, over a five month period 50,000 birds per day were killed. This turned out to be one of the last large nesting areas in North America. As this fact became apparent, a bill was finally passed making it illegal to trap pigeons within two miles of their nesting area.

By 1890, the wild passenger pigeon was nearly completely eradicated. In 1897, the Michigan state legislature passed a bill putting a ten year ban on the killing of passenger pigeons. But it was too late. Seventeen years later, the last known living passenger pigeon would die alone in her cage. This bird, Martha, had once been part of a pair, with her male counterpart George, but he had died several years before. So, for the final years of her life, Martha sat in her one-bird cage alone. The Cincinnati Zoo offered a thousand dollar reward (about $30,000 today) to anyone who could track down a mate for Martha. Unfortunately, all her kind were dead. On September 1, 1914, Martha, the last known passenger pigeon, died at the Cincinnati Zoo. Just like that, a bird that numbered in the many billions about a half century before, was gone.