Ameiurus nebulosus

Common Name(s)





Catfish occur in slow flowing streams, wetlands and in the vegetative zone of lakes. They can tolerate a wide range of environmental conditions and they can also stay alive for extended periods out of water (if kept moist). Catfish prey on small native fish and fish eggs and compete with koura (native crayfish) which they also occasionally prey on.


Catfish are dark brown to green in colour, of medium size with sharp spines at the front of the pectoral and pelvic fin and have distinct whisker-like feelers, also called barbels.

Similar Species

Unlikely to be confused with other species present in New Zealand. No similar species in New Zealand (but there are 45 catfish species worldwide)

Threat To Plants

Catfish can have negative effects on water quality as they stir up sediments (while searching for food); these sediments then cloud the water and can disrupt ecological processes related to aquatic plant communities.


Widespread in the Waikato River catchment (including Lake Taupo). Isolated populations in Northland, Wairoa, Whanganui and Hokitika.


weight:<2kg; body lenght: <40 cm

Year Introduced


Reason For Introduction

Food and game

Colonisation History

Catfish were first introduced to New Zealand in St John’s Lake near Auckland in 1877. Around 1885, further releases were made in Wellington and Hokitika. For the next hundred years, little further spread was detected until, in 1985, catfish were first found in Lake Taupo—but it is unknown if this was an accidental or deliberate introduction. Since then, catfish have gradually spread down the Waikato. In 1997, catfish were also recorded from the Kaituna Lagoon near Lake Ellesmere and from a stream entering Hokianga Harbour in 2003.

Control Options

Pond drainage, trapping, cube root powder