Sydney Rock Oysters
Sydney Rock Oysters' (Saccostrea glomerata)
have a thick shell with a smooth exterier surface
which can grow to 8 cm in length. The outside of their shell is smooth and grey coloured. The inside of the shell is smooth and white coloured. There are hinge teeth on the inner margin of their upper shell. The mantle edges and adductor muscle scar are pale coloured.
Sydney Rock Oysters are found on the south-east coast of Australia living near the mouths of rivers. They are capable of tolerating a wide range of salinities. They are usually found in the intertidal zone to 3 metres below the low water mark. Adults live attached to rocks. They eat phytoplankton, zooplankton, bacteria and organic matter by filtering water into their shells and straining the microorganims out.
Their predators are birds, fish (e..g bream), stingrays, octopus, mud crabs, whelks and sea stars.