Harris' mud crab (Rhithropanopeus harrisii) competes with native species and can spread crustacean diseases. It can damage the catch in fishing nets and clog water intake pipes.
What to look for
- greenish brown to olive green
- white-tipped claws, unequal size
- hairy abdomen
- 4 spines on each side of body
- slight notch between the eyes
- eyes not at the widest point of the body
- body about 1–2cm wide
- often found in dense groups.
Where to look
Look on or around:
- fishing nets
- rocks and stones
- vegetation and oysters
- water intake pipes.
Likely habitats include:
- salt, brackish or fresh water
- shallow waters.
Similar native species
These native species look similar to Harris' mud crab. It does not need to be reported.
River swimming crab (Varuna litterata)
- red-brown body
- body up to 5.5cm wide
- claws are the same size
- 3 spines on each side of body
- flattened legs
- legs covered with long hair on inside edge of last 2 segments.
- can live in fresh or salt water
- prefers sandy areas with high tidal flushing.
See something unusual? Report it. Even if you’re not sure.
If you see something you think is a pest:
- note the exact location
- take a photo (use something for size reference, like a coin or note)
- contact your state or territory authority.
Stop the spread of marine pests
Start with these simple steps:
- Inspect and clean your boat or yacht. Make sure you check hard to reach areas.
- Treat the hull of your boat or yacht regularly.
- Clean and dry your fishing and diving gear after every use.
How you can stop the spread of marine pests.
The map shows known pests and pests to look for around Australia.