The ORC’s Environmental Data Portal is experiencing high traffic volumes affecting its effectiveness at present. The site is being worked on at present and people are asked to be patient. Please be considerate in using this tool, some people require access to the EDP for important decision-making today.
Environmental Data PortalThe ORC’s Environmental Data Portal is experiencing high traffic volumes affecting its effectiveness at present. The site is being worked on at present and people are asked to be patient. Please be considerate in using this tool, some people require access to the EDP for important decision-making today.
Common name: | Asian paddle crab |
Scientific name: | Charybdis japonica |
Management programme: | Unwanted Organism |
If you have seen or suspect the presence of this pest you must report the sighting to us.
Contact Otago Regional Council on 0800 474 082 or biosecurity@orc.govt.nz
The Asian paddle crab is an aggressive predator that competes with native crabs for space and food. They prey on a wide range of native species, including shellfish, fish, other crustaceans, and polychaete worms, posing a significant threat to local marine ecosystems. These crabs reproduce rapidly, with females producing up to 85,000 eggs multiple times a year. The larvae can survive in varying water temperatures and salinities, allowing them to spread over large distances via tides and currents.
Late spring to early autumn (October to March in the Southern Hemisphere). This period aligns with the warmer months when crabs are most active, feeding, and reproducing. Juveniles and adults are more mobile and visible in these months, making surveys more effective.
It is an offence to breed, knowingly communicate, exhibit, multiply, propagate, release, or sell, an unwanted organism (Biosecurity Act 1993).
ORC is currently developing a marine biosecurity programme and needs to obtain more information on species distributions before pursuing management options. If you think you have spotted Asian paddle crab, please let us know by calling 0800 474 082 or emailing biosecurity@orc.govt.nz
Preventing the spread of Asian paddle crab is the best strategy, as removal of invasive marine pests is both difficult and expensive.
Cleaning your craft and gear for biosecurity purposes is an important way to help protect the marine environment. Just as regular maintenance keeps your equipment in good condition, biosecurity cleaning keeps the ocean healthy for everyone.
The three main types of marine biosecurity cleaning for boaties are:
You must notify the Otago Regional Council if you suspect the presence of this organism.
If you think you've seen Asian paddle crab:
An unwanted organism is not managed under the ORC Pest Plan but may be controlled as part of our Biosecurity Strategy.
Do you know what’s lurking beneath your boat? The ORC Biosecurity team works hard to stop harmful pests from spreading in Otago’s coastline and helps people learn how to keep these pests out.