In maritime narratives of humans, ships and the sea, animals are too often absent, or marginalised in passing references, despite the fact that ships once carried, and were populated by, all kinds of animals. Horses, mules and other ‘military’ animals crossed the sea to their battlefields, while livestock were brought on-board to be killed and eaten. Sailors and passengers kept animal companions, ranging widely from cats and parrots to ferrets and monkeys. Animal stowaways, such as rats, termites and shipworms, did tremendous damage to ships’ structures and stores, especially during the age of sail. Rats also emerge from the archives as seafarers, ‘colonisers’ and explorers alongside their human counterparts. Moreover, countless animals – seabirds, dolphins, porpoises, etc. – would visit and accompany ships, filling many sea narratives with the wonder of oceanic animal encounters.