European shore crab
Portunidae - Carcinus maenas

What does it look like?

Adult specimen shells can reach widths of up to 8 cm, with five spines or spikes on each side of shell. Their colour varies from green top and yellowish underside, to red/orange mottled above and orangeor partly red underneath; juveniles generally lighter incolour than adults. There are also three rounded teeth or lobesbetween the eyes and no swimming paddles on its legs.

European shore crabs can be found in all types of protected and semi-sheltered marine and estuarine habitats, including mud, sand,rocky substrates and seagrassbeds from the intertidal to 60 m deep, although it is predominantly a shore to shallowwater species.

Why is it a problem?

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

Control Methods

You can help prevent the spread of marine pests by:

• Regularly cleaning your boat’s hull – ideally keep fouling growth to no more than a light slime layer.

• Applying good thorough coatings of antifouling paint and keep it in good condition

• Ensuring your hull is clean and free of fouling before you go travel to a new region

• Cleaning and drying any marine equipment (e.g. ropes, lines, pots) before using in a new location.

• Inspecting areas on your boat that retain water in case they’re harbouring marine life.

• Checking anchors, trailers and other equipment for tangled weeds.

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