Abstract
In 1730, Dutch dike authorities discovered a hitherto little-known species of shipworm (Teredo navalis) burrowed into the wooden revetments that protected coastal dikes. Further investigation revealed infestation was widespread across three provinces. This wood-boring mollusk undermined dike stability, threatening cities and valuable agricultural land. Fearing an existential disaster if dikes failed, authorities enacted a capital-intensive dike reconstruction programme, replacing wooden components with imported stone. This transformation is well known in Dutch water history and considered a pivotal moment in dike modernisation. Little scholarship explores the process of adaptation or the broader context of Dutch experience with the mollusk. Shipworms were a primary hazard of oceanic travel, and mariners had coped with them for centuries. Although dike authorities often emphasised the novelty of the threat, they nevertheless proposed, tested and implemented shipworm 'remedies' derived from this maritime knowledge. This chapter explores the challenges shipworms presented for both dikes and ships, the limitations of translating maritime adaptations to the coasts, and dike authorities' ultimate decisions to accept or reject these strategies. The shipworm animal bridged these two realms of adaptive experience. This integrated perspective presents a richer understanding of the process of dike adaptation.