Overview
Sea serpents are among the oldest monsters on record. Sailors from Norway to New England to the South Atlantic reported long, snake-like animals with manes, humps or horse-like heads. In 1555 Swedish churchman Olaus Magnus described a Norwegian serpent hundreds of feet long living in caves near Bergen. In 1734 missionary Hans Egede reported a monster off Greenland that rose higher than his ship's mast.
The kraken is the serpent's many-armed cousin, from Norwegian lore. A 1646 glossary first described it as a sea monster with many arms that drags boats into the deep. Bishop Erik Pontoppidan spread its fame across Europe in his 1752-53 Natural History of Norway. Most scholars now trace the kraken to the giant squid, a real animal that can reach about 10.5 meters in length, which was finally photographed alive in its habitat in 2004.
Two reports stand out. In August 1817 dozens of people at Gloucester and Cape Ann, Massachusetts, reported a serpent in the harbor, and a scientific society took sworn statements. In August 1848 the captain and officers of the Royal Navy's HMS Daedalus reported a sixty-foot serpent in the South Atlantic, sparking a public debate in The Times.
Proposed explanations include oarfish, giant squid, sei whales, seals, lines of porpoises, floating debris and whales tangled in fishing gear. Some researchers still think an unknown large marine animal may explain the best reports.
Timeline
- 1555Olaus Magnus describes the Norwegian sea serpent.
- 1638-39John Josselyn records a sea serpent off Cape Ann, Massachusetts.
- 1646Christen Jensøn's glossary gives the first written description of the kraken.
- July 6, 1734Hans Egede reports a sea monster off Greenland.
- 1752-53Erik Pontoppidan's Natural History of Norway popularizes the kraken.
- 1802Pierre Denys de Montfort publishes his famous image of a giant octopus attacking a ship.
- Aug 1817Gloucester sea serpent flap; Linnaean Society of New England investigates.
- Aug 6, 1848HMS Daedalus sighting in the South Atlantic.
- Dec 31, 1848Sighting from HMS Plumper off Portugal.
- 1857Japetus Steenstrup names the giant squid genus Architeuthis.
- 1892A.C. Oudemans publishes The Great Sea-Serpent.
- Oct 1937Naden Harbour carcass, British Columbia.
- Sept 30, 2004Kubodera and Mori photograph a live giant squid.
- June 19, 2019NOAA expedition films a juvenile giant squid in the Gulf of Mexico.
Reported sightings
Coast near Bergen, Norway
1555 (published) Told story
In his History of the Northern Peoples, Olaus Magnus described a sea serpent said to live in caves along the Norwegian coast near Bergen. He gave it a length of two to four hundred feet, a mane of long hair, sharp black scales and flaming red eyes. He was recording sailors' and coastal lore.
Source: en.wikipedia.orgOff the coast of Greenland
July 6, 1734 On the record
Missionary Hans Egede reported a huge sea monster that raised itself higher than the ship's mainmast. He described a long, sharp snout, spouting like a whale, broad fins, and a tail that rose a whole ship-length from the head. Naturalist Henry Lee later argued it was the head and a tentacle of a giant squid.
Source: en.wikipedia.orgOff Cape Ann, Massachusetts
1638-1639 On the record
John Josselyn recorded a sea serpent off Cape Ann. Wikipedia calls it the first American sea serpent. The report foreshadows the much larger flap in the same waters nearly two centuries later.
Source: en.wikipedia.orgGloucester harbor and Cape Ann, Massachusetts
August 1817 Investigated report
Fishermen, townspeople and the crew of the schooner Caravan reported a serpent-like creature about sixty feet long, with a head compared to a turtle's or a horse's and a humped back. The Linnaean Society of New England sent out questionnaires, took statements and published a report the same year, making it one of the best-documented sea serpent cases. Joe Nickell later suggested a narwhal for reports of a spike on the head.
Source: en.wikipedia.orgNear Cape Ann, Massachusetts
Late 1817 On the record
A small, oddly humped snake was found and presented by the Linnaean Society as the young of the great serpent, under the new name Scoliophis atlanticus. Critics quickly said it was an ordinary land snake, and it was later identified as a common black racer whose humps came from disease. The mistake embarrassed the society.
Source: en.wikipedia.orgSouth Atlantic, between the Cape of Good Hope and St Helena
Aug 6, 1848 On the record
Captain M'Quhae and officers of HMS Daedalus watched a creature pass close to the ship for about twenty minutes. They estimated sixty feet of body at the surface, a snake-like head held about four feet above the water, a diameter around sixteen inches, dark brown color with a yellowish throat, and something like a horse's mane or seaweed along its back. It held its course at an estimated 12 to 15 mph. The report ran in The Times and set off a public argument.
Source: en.wikipedia.orgOff the coast of Portugal
Dec 31, 1848 On the record
An officer of HMS Plumper reported a long black creature with a sharp head, with about twenty feet of its back showing. A drawing titled Supposed Appearance of the Great Sea-Serpent, from H.M.S. Plumper was published soon after.
Source: en.wikipedia.orgNaden Harbour, Haida Gwaii, British Columbia
October 1937 On the record
Whalers found a strange carcass in the stomach of a sperm whale and photographed it. It was hailed as a young 'Caddy', the Pacific coast serpent Cadborosaurus. The provincial museum director, Francis Kermode, tentatively identified it as a fetal baleen whale.
Source: en.wikipedia.orgStrait of Georgia, British Columbia
1943 On the record
Inspector Robert Owens and Staff Sergeant Jack Russell reported a huge sea serpent with a horse-like head. On closer look it proved to be a big bull sea lion leading a line of six others, a neat example of how a group of animals can look like one long body.
Source: en.wikipedia.orgPacific Ocean, about 600 km south of Tokyo
Sept 30, 2004 On the record
Japanese scientists Tsunemi Kubodera and Kyoichi Mori lowered a baited camera to 900 meters and photographed a live giant squid about eight meters long. It fought the line for four hours and escaped, leaving a 5.5-meter tentacle behind. It was the first time the animal behind the kraken legend was photographed alive in the wild.
Source: en.wikipedia.orgEvidence
Linnaean Society report (1817) Unexplained
Sworn statements on the Gloucester serpent; a formal published report.
Scoliophis atlanticus specimen Explained
Presented as a baby sea serpent; actually a diseased black racer snake.
HMS Daedalus report and engravings (1848) Disputed
Detailed report by naval officers; explanations proposed include a sei whale.
Naden Harbour carcass (1937) Disputed
Photographed carcass; tentatively identified as a fetal baleen whale.
Giant squid photos and video (2004, 2012, 2019) Explained
Confirm a real deep-sea giant matching much of the kraken lore.
Bermuda oarfish (1860) Explained
A long oarfish washed ashore; oarfish are widely proposed as serpent sources.
What each side says
What witnesses and researchers report
Many sea serpent witnesses were trained observers: naval captains, officers, ship crews and scientists. The Daedalus officers watched for twenty minutes in daylight and filed an official report. In Gloucester, many people gave sworn statements to a scientific society.
Researchers such as A.C. Oudemans in 1892 gathered hundreds of reports and argued they point to a real, unknown animal. The kraken story shows that sailors' monsters can turn out to be real: the giant squid was dismissed as myth for centuries before it was caught on camera.
What skeptics and scientists suggest
Scientists propose known animals. The giant oarfish is long, ribbon-like and swims with a wave-like motion. Biologist Gary Galbreath argues the Daedalus crew saw a sei whale. In 2016 researcher R.L. France suggested whales tangled in fishing gear and debris, and Karl Brandt in 2023 suggested harpooned sperm whales dragging overturned boats.
Lines of seals, sea lions or porpoises can look like one long animal with humps, as the 1943 British Columbia case showed. Gloucester's spiked head fits a narwhal, according to Joe Nickell, and the Linnaean Society's 'baby serpent' was just a sick land snake.
Open questions
- What did the Daedalus officers see in 1848?
- Could any large marine animal still be undiscovered?
- How many serpent reports were giant squid at the surface?
Visiting
Where: Gloucester and Cape Ann, Massachusetts, home of America's most famous sea serpent; Bergen, Norway, the setting of Olaus Magnus's serpent.
Access: Gloucester's harbor and waterfront are public. Many natural history museums display preserved giant squid.
Events: None confirmed.
Did you know?
- In 1845 Albert Koch displayed a 35-meter 'Hydrarchos' fossil skeleton presented as a sea serpent.
- The coat of arms of Seljord in Norway shows a sea serpent.