“The CarP‐N neutral Project”: removal, processing and reuse of invasive fish in local terrestrial conservation projects

1. Proliferation of problematic non-indigenous fish species is major biosecurity problem in many countries.
2. In Southern Hemisphere lowland rivers, species such as introduced common carp (Cyprinus carpio) take advantage of nutrient rich conditions and a temperate climate and often dominate the fish biomass in invaded waterbodies.
3. These invasive organisms assimilate nutrients into their flesh and also release nutrients through re-suspension and defecation re-directing the pathway of energy transfer and use in aquatic systems.
4. We describe an invasive fish ‘recycling’ programme where a semi-automated trap selectively captures pest fish and transfers them to a thermophilic digester where bacteria efficiently process them into nutrient rich meal.
5. Developing products from invasive fish meal to support other conservation efforts while simultaneously providing a funding source to offset the costs of harvest and de-incentivise spread are key objectives.
6. We showcase two trials ...