The zaratan (Arabic saraṭān, “crab”) is a giant sea creature from medieval Arabic literature, so large that sailors mistook it for an island. They would land on it, explore its woods and valleys and light a fire, only for the “island” to feel the heat and glide away or sink beneath them. Today the zaratan is usually pictured as a colossal turtle, but that image owes much to the twentieth-century writer Jorge Luis Borges; in the Arabic sources its name means “crab.” The zaratan belongs to a family of island-monsters found across the medieval world, from the Greek Physiologus to Irish saints’ tales and Norse sagas, and a 2023 study suggests that some of these legends may preserve real observations of feeding whales.[1][2][3]
| Tradition | Medieval Arabic literature and sailors’ tales |
|---|---|
| Name | Arabic saraṭān, “crab”; the spelling “zaratan” was popularized by Borges |
| Earliest source | Al-Jahiz, Kitāb al-Hayawān (Book of Animals), 9th century |
| Other sources | Al-Qazwini, Wonders of Creation; the first voyage of Sinbad in the Thousand and One Nights |
| Story | Sailors land on an “island,” light a fire, and the creature moves away or sinks |
| Relatives | Aspidochelone, Jasconius, fastitocalon, lyngbakr and hafgufa |
| Natural explanations | Whales, including trap-feeding behavior; tidal “vanishing islands” |
A skeptic’s first account
The earliest known account of the zaratan comes from one of the greatest writers of the Abbasid age, the Basran polymath Al-Jahiz, in his ninth-century Kitāb al-Hayawān, the Book of Animals. He listed three monsters said to live in the sea: the tanin (sea-dragon), the saraṭān (crab) and the bala (whale). He was frank about the zaratan: he had never met anyone who could assure him he had seen it with his own eyes. Sailors, he wrote, claimed to have landed on islands with woods, valleys and fissures and lit a great fire, at which the monster began to glide away with them and all the plants growing on it, so that only those who fled were saved. In Al-Jahiz’s judgment, this tale outdid “the most fabulous and preposterous of stories.”[1]
Al-Qazwini and Sinbad
Later writers were less doubtful. The thirteenth-century cosmographer Zakariya al-Qazwini included the creature in his Wonders of Creation, an encyclopedia of marvels of the natural world. And the island-monster appears in one of the most famous stories ever told: the first voyage of Sinbad the Sailor in the Thousand and One Nights. Sinbad and his shipmates land on what looks like a small green island, light fires to cook, and are thrown into the sea when the “island,” in fact a great sea creature, wakes and dives. Sinbad is left behind in the sea, but survives to continue his adventures.[1][2]
How the zaratan became a turtle
In Arabic, saraṭān means “crab,” the same word used for the zodiac sign Cancer. The modern image of the zaratan as a giant turtle seems to come largely from the Argentine writer Jorge Luis Borges, who included it, spelled “zaratan,” in his Book of Imaginary Beings. Borges cited Al-Jahiz, noted his skepticism and contrasted it with al-Qazwini’s more credulous account, and described a long-lived creature whose shell could easily be mistaken for an island. The turtle form may also have been influenced by the closely related Greek aspidochelone, whose name contains the Greek word for turtle. From Borges, the turtle zaratan passed into fantasy fiction and games such as Dungeons & Dragons.[1][2]
Earlier versions of this entry presented the zaratan as primarily a turtle in Arabic tradition and described it as both benevolent and predatory in “global” folklore. Those details reflect modern retellings rather than the medieval sources.
The island-monsters of the medieval world
The zaratan is one of many creatures in medieval literature that sailors mistook for islands. The stories are strikingly similar, and many probably share a common ancestor.[2]
- Aspidochelone. The oldest known version appears in the Greek Physiologus of the second century AD: a great whale with what look like beaches on its hide, which sailors moor to and build fires on, until it feels the heat and drags their ship into the depths. Its name combines Greek aspis (asp or shield) and chelone (turtle). In Christian allegory, it stood for Satan deceiving those he sought to devour.[2]
- Alexander and the Talmud. The Alexander Romance tells of companions of Alexander the Great drowning when an “island” turned out to be a monster, and the Babylonian Talmud records Rabbah bar bar Hana’s tale of a fish with sand and grass on its back, which turned over when travelers cooked on it.[2]
- Jasconius. In the medieval legend of the Irish Saint Brendan, the voyagers celebrate Easter on an island, light a fire and flee to their boat when it moves; Brendan explains that it is the great fish Jasconius, forever trying to put its tail in its mouth.[2]
- Fastitocalon. The Old English poem The Whale in the Exeter Book tells the same story under the name fastitocalon, a name later borrowed by J. R. R. Tolkien for a comic verse.[2]
- Lyngbakr and hafgufa. In the Icelandic Örvar-Odds saga, a heather-covered island and two rocks in the Greenland Sea turn out to be the monster whale lyngbakr and the vast hafgufa, sometimes linked to the Kraken.[4]
Were the island-monsters whales?
For centuries the obvious natural candidate for these stories has been the whale. The Physiologus itself calls the aspidochelone a whale, and whales basking at the surface, encrusted with barnacles and sometimes trailing seaweed, can look like low rocks or islets. Islands that appear and disappear with the tide, known as vanishing islands, may also have contributed to sailors’ tales.[2][5]
In 2023, a team led by John McCarthy of Flinders University, Australia, publishing in Marine Mammal Science, went further. They pointed to “trap feeding,” first recorded by scientists in 2011 off Vancouver Island, Canada, in which humpback whales float almost motionless with their mouths open at the surface, waiting for fish to swim in. The Physiologus says the aspidochelone exhales a sweet-smelling odor to lure small fish into its open mouth before snapping it shut, and the thirteenth-century Norse King’s Mirror describes the hafgufa in similar terms. The researchers suggest these texts may be describing trap feeding, observed by sailors up to two thousand years before scientists noticed it. McCarthy said he first thought the resemblance “was just an interesting coincidence.”[3]
Our assessment
The zaratan is a creature of literature and sailors’ yarns, not an undiscovered animal, and even its first chronicler, Al-Jahiz, called the story preposterous. It belongs to a remarkable family of island-monsters shared by Greek, Arabic, Jewish, Irish, English and Norse writers, which probably spread along trade and literary routes and drew on real sightings of whales. Its modern turtle form is largely the work of Borges, and the newest science suggests that behind the legend there may be real whales, feeding with their mouths open on the surface of the sea.
References
- “Zaratan,” Wikipedia, citing Al-Jahiz, Kitāb al-Hayawān; al-Qazwini; and J. L. Borges, The Book of Imaginary Beings.
- “Aspidochelone,” Wikipedia, citing the Physiologus, the Alexander Romance, the Talmud (Baba Batra 73a), the Navigatio of St Brendan and the Old English The Whale.
- “Legendary beasts in ancient literature may have been whales gulping down fish,” Natural History Museum, London (28 February 2023), on J. McCarthy et al., Marine Mammal Science (2023).
- “Lyngbakr,” Wikipedia.
- “Vanishing island,” Wikipedia.
Correction note (October 2026): This entry was rewritten from documented sources. Earlier versions presented the zaratan as a turtle of “global maritime folklore”; in the Arabic sources its name means “crab,” and the turtle form largely comes from Borges. The illustration above is an artistic impression.