The destructive work of Isopods is one of the most easily recognisable of marine borers. Examples of Isopods are Limnoria and Sphaeroma, both of which are prevalent along the east coast of Australia, north of Bateman’s Bay. The damage that they cause is typified by “hour-glassing” of marine timber piles. They burrow into the timber, at a shallow depth of up to half-an-inch. Eventually the timber breaks off and the cycle repeats again.
Sphaeroma are typically active within the tidal zone and are mostly responsible for the hour-glass appearance of timber piles. Limnoria are active over all depths and consume timber for food, unlike Sphaeroma, which is a filter feeder, and burrows into the timber for shelter.