Shipworms – so named because they riddled wooden vessels with worm-like burrows – are not worms at all, but highly specialised wood-eating bivalves. For centuries they represented one of the greatest threats to maritime safety. Their capacity to rapidly degrade timber shaped naval engineering, trade routes, and the fate of empires. Christopher Columbus was famously marooned in Jamaica in 1503 after shipworm damage rendered his vessels unseaworthy. The persistent threat of shipworms drove one of the Royal Navy’s most transformative innovations: copper sheathing, or “copper-bottoming,” which protected hulls and underpinned British naval dominance. With the transition to iron and steel hulls, the large-scale strategic threat posed by shipworms diminished. Today, their maritime impact is concentrated in artisanal fisheries, coastal infrastructure, aquaculture installations, and submerged cultural heritage, where damage to wooden structures is still estimated to cost billions annually.
Viewed solely through this lens, shipworms remain pests. Yet this is only part of their story. Ecologically, they are primary processors of terrestrial wood entering marine systems, preventing waterways from becoming choked with debris and sustaining complex coastal and deep-sea food webs. Biologically, their bacterial symbionts are at the forefront of antibiotic discovery and lignocellulose bioconversion research. Most recently, shipworms have been reimagined as candidate aquaculture species – low-input bivalves capable of converting waste wood into high-protein biomass at industry leading rates.
Understanding shipworms, therefore, is not only a matter of maritime protection, but of recognising a group of organisms that have shaped human history and may yet contribute to sustainable futures.
