Museum of Natural Mystery – Small Wonder # 4: The Sea Monster of Soay


Fear and sensationalism can make monsters out of any creature, but some animals don’t need help from tall tales to be terrifying.

In 1959, off the coast of Soay Island in Scotland, author Tex Geddes and engineer James Gavin encountered a monster while out shark-fishing. The men first heard the creature breathing, and upon turning toward the sound, found themselves face to face with a primal reptile of unimaginable horror. They described the creature as having a dark, rounded head with a red slash for a mouth, and lines of spiked structures contained within. Sharp, serrated ridges ran the length of its humped back. From what they could see of the animal above the water’s surface, they estimated it measured between 6-10 feet in length. Their account of the monster spread through Britain like wildfire, complete with a highly embellished, dragon-like illustration of the monster.


Okay, this is Gamera. The real illustration is the cover photo, but Gamera is a pretty close fit for their story.


In all the hype, the Soay Island Sea Monster took on a life of its own. The actual drawings of the creature by the two men who saw it were overshadowed, but they hold important clues to what the men may realistically have seen:


Tex Geddes (A) and James Gavin (B). Credit: Darren Naish by way of Bernard Heuvelmans.


It’s noteworthy that at first glance, Geddes thought the creature was a turtle, but later changed his mind as it drew closer. The size, spiked maw, and serrated back convinced him that the animal must be something much more unnatural. However, there are species of sea turtles with dorsal ridges similar to his drawing.


A Kemp’s ridley sea turtle. Note the ridges along the back.


In an article for Scientific American, paleontologist Darren Naish argues that it’s more probable that the men encountered the much larger Leatherback sea turtle.


Leatherbacks can grow to be truly massive. On average about 8 feet long.


But more importantly, look closely at the bumpy texture of those dorsal ridge lines.


The size and and shell structure might account for the enormity and serrated back of the Soay monster, but what about the mouth full of spikes? Well, have a look at this:



A Leatherback’s mouth is lined with spikey protrusions for snaring jellyfish.


Was the Soay Island Sea Monster a case of mistaken identity? When taken alongside the turtle’s size and anatomy, the evidence is pretty compelling. Perhaps Geddes and Gavin happened upon a Leatherback sea turtle as it breached the surface for air and, caught off guard by its genuinely startling features, let their imaginations conjure up something much more sinister.



The Soay Island Sea Monster of 1959 by Darren Naish

In the Wake of the Sea-Serpents by Bernard Huevelmans

Soay Sheep

St. Kilda World Heritage Site


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Museum theme by Michael Guy Bowman

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Emery Coolcats

Emery Coolcats

Podcaster. Extinct animal enthusiast. Host of Museum of Natural Mystery!
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