Maldives Tuna & Cowry Snails

Scientific Name:
Skipjack Tuna (katsuwonus pelamis)
Up to 7 years
Built for speed, with warm bodies and blood-rich muscles. Grow up to 3.6 ft long and 76 lbs.

cartoon words

By Richard King

globe identifying the location of the MaldivesThe earliest known written record of Maldives tuna is from the 1340s, left by the great Muslim traveler Ibn Battuta, who spent four years in the Maldives during his 30-year travel odyssey throughout Afro-Eurasia.

Ibn Battuta wrote: “The food of the natives consists of a fish… they call koulb al mâs. Its flesh is red; it has no grease, but its smell resembles that of mutton. When caught at the fishery, each fish is cut up into four pieces and then slightly cooked. It is then placed in baskets of coco leaves and suspended in the smoke. It is eaten when perfectly dry.” Battuta wrote that the tuna was then shipped to India, China, and Yemen.

The when, why, and how fishers from the Maldives archipelago, located a few hundred miles southwest of the southern tip of India, caught and dried their tuna is a surprising and ancient story, especially considering that it never would have become known so
broadly if it were not for a snail.

cowry climbing coral

The money cowry (Monetaria moneta) crawling upside on a rock underwater. |

Dr. Shreya Yadav and her research team out of the University of Hawai’i recently explained that the first human settlers of the Maldives lived the same way as many early settlers of other atolls, where water is scarce and coconut palms and a few other plants are the only tenable crops. For protein, perhaps in addition to seabird eggs, the settlers likely first turned to local fish and shellfish found in the coral reefs near shore, then began to sail farther out to capture tuna in deeper waters.

Sometime before 850 CE, centuries before Ibn Battuta’s travels, visiting Arabian and other international traders found in the Maldives a convenient port when sailing within their rapidly expanding network in the Indian Ocean. These traders discovered that the Maldives were blessed with prolific populations of a small saltwater snail called cowry, which became the first truly global, cross-cultural currency.

cartoon drawing of quarter and cowry shell

Maldivian dollar bills feature images of the tuna fisheries.

Like the coins that later replaced them, cowry are small, they stay shiny, and their available population was finite and controllable for a full millennium. Cowry shells served as money throughout the Indian Ocean region, into Africa and the western Pacific Rim, and even into Europe. Fishers throughout the Maldives—especially women—raised and harvested cowries from constructed floats of wood and branches, an early aquaculture. As Ibn Battuta traveled throughout the Middle East and parts of India in the 1300s, he wrote of the use of cowry shells and how the people of the Maldives remained the major global supplier.


The regular commercial ship traffic in and out of the Maldives to retrieve cowries helped expand the tuna fishery because it provided trading pathways. Dried tuna can remain edible for months, even years if stored properly. As Ibn Battuta explained, Maldivians boiled the tuna in saltwater—usually skipjack and less often yellowfin tuna—and then smoked hunks for shipping and storage. Because the Indian Ocean is so affected by stormy monsoon seasons, when fishing is more difficult, tuna were especially prized because they could be dried and kept on hand until the weather was safe for venturing out on the ocean again. In the centuries before refrigeration or canning, not only did dried tuna from the Maldives become a staple in local recipes throughout the cities and towns around the rim of the Indian Ocean, but the preserved fish might have also been a regular food source at sea for sailors, supplementing their regular menu of salted meats and sea turtle.

fishermen with long poles on flat boats tuna fishing

Maldivian fishers hooking skipjack tuna off the stern of their boats. | International Pole and Line Foundation.

Yadav and her research team explained that the fishers of the Maldives were able to capture tuna so successfully, in part, because they had a long history of building boats (using wood from coconut trees) in order to travel from island to island. They were also never more than a day trip from deep water because of the oceanography of their archipelago. The fishers of the Maldives baited their hooks with live smaller fish that they captured along the reefs on the way out, or the fishers simply chummed the water and brought in the tuna on baitless hooks. With communities focused on the offshore tuna fishery, a likely unintentional benefit in the Maldives was that people over the centuries had less environmental impact on local coral reefs.

Cartoon drawingFive hundred years after Ibn Battuta’s visit, the cowry trade began collapsing in the 19th century due to shell inflation (true story). Today, the low-lying archipelago is known more for tourism than fishing and for the imminent threat it faces from sea level rise. Yet with its snail-based currency long gone, the right to fish tuna has now become its own currency of sorts. In control of a huge ocean territory, the Maldives government earns income by selling the right to fish in its waters to other nations. Smaller Maldivian boats still fish primarily by pole and line, which eliminates bycatch and ensures the quality of the fish. As a result, the Indian Ocean tuna fisheries using this method have been certified as one of the most sustainable fisheries in the world, fished in nearly the same way that the great traveler Ibn Battuta observed nearly 700 years ago.

For more visit Animals in Sea History,, or the just-released book, Ocean Bestiary: Meeting Marine Life from Abalone to Orca to Zooplankton, a revised collection of over 17 years of this column!

“Sea History for Kids” is sponsored by the Henry L. & Grace Doherty Charitable Foundation

Did You Know?

Seal With Plastic Bottle

Marine animals consume plastic when they confuse it for food.

Small plastics and floating objects often look like food to aquatic animals and sea birds. When they eat plastic, it often gets stuck in their digestive system, making them feel full and unable to eat proper food.

What can YOU do?
Learn more at Getting Rid of Marine Debris