Data from: “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 to
substantiate our concept; a dune planting experiment where we demonstrate
the transfer of processed invasive fish nutrient from an over-fertilised
aquatic ecosystem to coastal sand dunes where nutrients are depleted but
were formerly higher. We also illustrate the potential for using this
locally derived recycled nutrient to replace imported synthetic fertiliser
tablets typically used in dune planting. 7. The second trial demonstrates
use of invasive fish as a lure in terrestrial trapping programmes for
controlling other problematic invasive pests. Synthesis and applications:
We consider this concept to be a shift in restoration thinking whereby an
aquatic biosecurity problem is being used to improve indigenous
biodiversity outcomes in other ecosystems. We propose that this project is
a useful vehicle to promote thought that more accurately embodies the
concept of sustainability by being more cognisant of the traceability of
nutrient flow from harvest and processing through to use within and
between ecosystems. It illustrates alternate ways in which invasive
products can be applied to these systems for positive environmental
outcomes and to generate programme cost recovery. A similar philosophy
should be applicable to problematic and abundant invasive species
elsewhere, particularly where those organisms are susceptible to either
point source control and or efficient mass harvest.08-Mar-2018