Fish-Tasting and Toxic Navigation: Life and Death at Sea in 1526

When we think of pilots’ technical writings, we tend to imagine raw materials—hurried notes, rough sketches, a synthetic and telegraphic style. So it comes as a surprise to encounter richly crafted codices, adorned with elegant graphic elements and beautiful handwriting. This is precisely the case with the Livro de Marinharia by Bernardo Fernandes, preserved at the Vatican Library. It is one of the oldest surviving nautical collections, comprising around forty texts—rutters, logbooks, nautical regulations, treatises, and questionnaires for pilots—dated between 1514 and 1548. These texts incorporate earlier knowledge and hands-on maritime experience, alongside insights from more recent long-distance voyages.

At the heart of this post is the logbook of the ship Conceição, which sailed from Lisbon to Goa in 1526. It provides a vivid account of daily life on board. In many logbooks, the rhythm of the journey is shaped by problems and setbacks. Pilots frequently report on the presence of the sick, the types of treatments administered, and even the deaths that occurred during the voyage. The journey of the Conceição is no exception and offers a striking case of poisoning.

The source of the poisoning was a type of fish consumed by the crew between the Angoche Island and the African coast. The author of the logbook wrote that the sailors who had gone ashore to fetch water caught some small fish resembling the peixe-sapo (anglerfish, fam. Lophiidae), of which about three men died immediately, and the other three, when they returned to the ship, were already swollen. The account also mentions the use of theriaca, the theriac of ancient physicians, a complex antidote used in early medicine, which was considered especially useful against animal venom and stomach aliments, to save the three men. The symptoms and context suggest that a toxic species, possibly a pufferfish (fam. Tetraodontidae) or toadfish (fam. Batrachoididae), was mistakenly consumed during the voyage. Especially, the consumption of pufferfish could lead to symptoms like swelling, paralysis, and death. [Luana Giurgievich]