Fisheries Western Australia is urging crabbers to be wary of the Asian paddle crab, a non-native pest species, when trawling the waters this summer.
It can also carry diseases that are poisonous to humans.
The Asian paddle crab can be noticed by its pale to olive green colour, and are likely to be found in estuaries and lower reaches of rivers.
Fisheries are asking anglers to double-check their species as the paddle crab can be mistaken for undersized mud crabs.
The paddle crab is not currently established in Australia, but has significant potential to do so and to become a major pest, so it is important to immediately report any found in the wild.
While only five of the species have been sighted in Western Australian waters since 2010 – one in Mandurah and four in the Swan River – Fisheries are urging crabbers to remain vigilant against the threat.
Anyone who comes across one of these crabs is urged to retain the animal, record the location (including GPS readings if possible) and call FishWatch on 1800 815 507.
Visit fish.wa.gov.au for more information on the Asian paddle crab or how to report a sighting.