If you see an Asian paddle crab on your travels, you are unlikely to see many other species close by. It is aggressive and quickly out competes our native paddle crabs for space and food. With a vicious bite when disturbed, the adults are strong swimmers and can spread attached to fouling on a boats hull, or as larvae in sea chests or ballast water where they can live for up to a month.

How to identify this species:

• Large swimming crab

• Shell ~12cm across

• Six spines on shell

• Five spines on claws

• Pale green-olive green

• Deep brown to purple

This species is known to be in the following locations in Northland, Auckland and Bay of Plenty.

Hokianga Harbour, Houhora Harbour, Waikare Inlet,  Ngunguru, Tutukaka, Whangārei Harbour,  Hauraki Gulf; Waitematā Harbour, Tamaki Estuary; Aotea - Great Barrier Island, Kaipara Harbour; Manukau Harbour; Tauranga Harbour, Ohiwa Harbour, Raglan Harbour

This list is correct to the best of our knowledge at the time of publishing - for a full list of marine pest locations, please go to the Marine Biosecurity Porthole If you find it outside this area, please report it.