Wood boring molluscs of the Palk Bay and the Gulf of Mannar

Abstract

The incidence and activity of eleven species of shipworms (Bivalvia: Teredinidae) and two species of piddocks (Bivalvia: Pholadidae) in several localities along the coasts of the Gulf of Mannar and the Palk Bay, are reported. The borer activity and nature of timber destruction are noted in aquafarms where Teredo furcifera von Martens, T. fulleri Clapp, T. bartschi Clapp and Lyrodus pedicellatus (Quatrefages) are active. In floating timbers from the open sea Bankia campanellata Moll and Roch, B. carinata and Martesia fragilis are found to be common. Less important forms included such species as Teredo triangularis Edmondson, Teredora princesae (Sivickis), Uperotus clavus (Gmelin), U. rehderi (Nair), Teredothyra excavata (Jeffreys) and Martesia striata (Linnaeus). The incidence of these pests and the relative destruction of timber structures in different mariculture farms varied with locality. The possible causes for the severe attack, nature of vertical distribution, factors affecting the spatial variations and the possibilities of prolonging the service life of indigenous timbers in coastal waters are discussed briefly