Teredos as pests

Before the advent of man, teredos lived in fallen trees in the sea. When man began building wooden ships and wharves, teredos became pests. Archimedes of Syracuse protected his ships by a sheathing of lead. Copper sheathing was first used by the British in 1758 to protect their ships (from teredos, borers and fouling organisms). In the days of the clipper ships, nearly all vessels sailing in tropical seas were sheathed with copper, a very expensive practice, but with the advent of metal ships the problem of teredos ended. Teredos are still a problem for wooden ships, small fishing and pleasure boats, and specialized ships such as minesweepers. For waterfront installations, teredos are a significant though decreasing problem as more and more wharves and piers are constructed of steel and concrete. The Dutch were the first to be greatly concerned at such destruction. In the 18th century, severe infestations of teredos, attacking the wooden parts of locks and dykes, threatened the existence of much of their countryside. Of the most recent attacks by teredos, the most famous was that in San Francisco bay during 1917-21, when $25 million worth of destruction was caused to wharves and jetties.