Polyurethane coated timber specimens are being attacked at Townsville by Sphaeroma terebrans in the tidal zone. To understand this marine borer better, the results from several other marine tests at Townsville are briefly described, and information about Sphaeroma spp. from elsewhere in Australia is presented. At Townsville, Sphaeroma seems to prefer the shady side of timber fender piles. Also, it is rarely found below the tidal zone. After two years, CCA-treated slash pine mooring piles were lightly attacked, and after 5.7-8 years eight double-treated eucalypt fender piles were only lightly attacked, while three were moderately attacked in the tidal zone. Untreated turpentine piles last about 10-16 years in Townsville, due to the damage caused by Sphaeroma. At nearby Bowen, Sphaeroma terebrans in two experimental piles died after the piles were pulled from the sea, and took more than 3 years to recolonise the piles after they were reinstalled. During this time after reinstallation, the original Sphaeroma terebrans holes were inhabited by Sphaeroma walkeri, a non-wood borer. At a brackish water test site at Port Stephens, Sphaeroma is more often found below low tide. It also prefers to bore upwards rather than downwards, perhaps to lessen the amount of silt entering its burrow. In the southern state of Victoria, Sphaeroma is not an economic problem, causing only minor etches and few holes. There in the tidal zone, it can scallop out disused longicorn beetle emergence holes to give an unusual pattern of attack on the pile surface.

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