The presence of a number of species of isopod borers (Limnoriidae family) in seagrass species from south-western Australia were documented from sampling seagrass tissue from Rottnest Island. The abundance of isopods within seagrass meadows at Rottnest Island was estimated and the appearance of seagrass invaded by isopods and tissues consumed by these isopods are described. However seagrass from other locations were also studied. These locations included: Bremer Bay, Esperance, Fremantle, Shark Bay, Marmion, Geraldton, Peaceful Bay, Geographe Bay.