European shore crab

What does it look like?

Adult European shore crabs can reach up to eight centimetres wide and have five spines on each side of the shell. Their colouring varies, ranging from a green upper shell with a yellowish underside to a red or orange mottled upper shell with an orange or partly red underside. Juveniles are lighter in colour than adults. They also have three rounded teeth or lobes between the eyes and do not have swimming paddles on their legs.

European shore crabs are found in a wide range of protected and semi sheltered marine and estuarine habitats, including mud, sand, rocky substrates and seagrass beds. They occur from the intertidal zone down to depths of up to 60 metres but are most commonly found in shallow coastal waters.

Why is it a problem?

The European shore crab is a highly adaptable and is an invasive species. It has a varied diet, eating mussels, crabs, oysters, limpets, barnacles, worms, juvenile crabs and shellfish including scallops. This species has the potential to significantly alter ecosystems causing mortality in native crab and shellfish populations.  European shore crabs have been implicated in the decline of native shellfish populations overseas, with some species of commercial importance.

Control methods

You can help prevent the spread of marine pests by:

• Regularly cleaning your boat’s hull –keep fouling growth to no more than a light slime layer.
• Applying a thorough coating of antifouling paint and keep it in good condition
• Ensure your hull is clean and free of fouling before you go travel to a new area
• Clean and dry any marine equipment (e.g. ropes, lines, pots) before using in a new area.
• Inspect areas on your boat that retain water for signs of marine life.
• Check for aquatic weeds tangled around anchors, trailers and other equipment.

Related links

• MPI listing
• Marine biosecurity porthole listing