Navigation for Our Changing World

Koi carp and CarpN Neutral

The CarpN Neutral programme run by the Waikato Regional Council aims to remove as many koi carp as possible from Waikato's lakes and use a biodigestor to turn their bodies into a useful compost for native revegetation projects

Bruno David with koi carp photo Alison Ballance RNZ

Lake Waikare fish trap and CarpN Neutral biodigestor photo Alison Ballance RNZ

Koi carp photo Alison Ballance RNZ

Bullhead catfish - another introduced pest fish photo Alison Ballance.JPG

Bacteria-rich starter used to break down koi carp photo Alison Ballance.JPG

CarpN Neutral biodigestor photo Alison Ballance.JPG

Biochar made from corn is mixed in with the 'carpuccino' made from biodigested koi carp photo Alison Ballance.JPG

The final result - sacks of fertiliser pellets made from koi carp photo Alison Ballance.JPG

The images in this gallery are used with permission and are subject to copyright conditions.