A bivalve mollusc, of the family Teredinidae, also known as a shipworm because of the damage they cause to any wood in the sea. They bore long cylindrical holes in the wood, digesting the wood they carve out. They have digestive enzymes that are able to break down cellulose; most other woodborers rely on symbiotic micro-organisms to break it down. The tunnel connects to the outside water via a tiny hole through which the teredo obtains the oxygen it needs. A fully grown teredo can be nearly a metre in length, and carve a hole 2.5 cm (1 in.) in diameter. They occur at all depths in all seas, but are most common in warmer seas. During the 18th century wooden-hulled vessels were clad with copper sheathing to prevent teredo infestations, which could cause catastrophic failure of the ship's timbers. Special paints have been developed which, when applied to the hulls of ships, deter both teredos and fouling organisms, but these have raised serious environmental issues and the International Maritime Organization has begun a process which will ban them.
M. V. Angel
Subjects: Maritime History.