MenuMain navigation

Freshwater biosecurity

Invasive aquatic pests are radical transformers of aquatic ecosystems. Their impacts include degraded water quality, reduced native biodiversity and local extinctions, damaged or obstructed hydropower and irrigation infrastructure, and reduced waterfront property values. The impacts of invasive aquatic pests are self-escalating as their populations increase and ranges expand. The threats posed by invasive aquatic pests are a perennial concern for both the New Zealand public and the agencies responsible for managing these pests.

The goal of the Freshwater Biosecurity programme is to support the New Zealand Biosecurity Strategy by reducing the risk of new freshwater invasive species incursions and establishment, minimising the adverse impacts of established populations of these species, and developing methods for reducing or eradicating those populations.

Programme Leader: Dr Deborah Hofstra


Biosecurity risks - advance risk assessment, prediction and modelling.

  • Identify potential and emerging threats to New Zealand's freshwater ecosystems from invasive non-indigenous species.
  • Investigate the mechanisms by which invasive species are transported, become established and adversely impact core environmental, economic, social and cultural values.
  • Model alternative potential outcomes to visibly demonstrate the impacts and associated costs that may be averted by proactive biosecurity actions.

Tools to respond – enable predictable management of pests and mitigation of the impacts of invasive species

Core to a successful biosecurity response is knowing where, when and how to respond.

  • Develop surveillance capability and remote sensing tools for detection of high-risk aquatic species.
  • Develop best practice tools for preventing the establishment of, or eradicating newly arrived species, and mitigating impacts of established pests. 
  • Report on the current state of lakes and invasive species.  

Thresholds and interventions – understand ecosystem thresholds and values and set management goals.

  • Investigate links between biosecurity interventions and freshwater restoration outcomes. 
  • Understand ecosystem thresholds and values to support the setting of management goals.

Biosecurity exchange – a collaborative approach with stakeholders.

  • Understand stakeholder needs to inform research directions. 
  • Optimise biosecurity outcomes for NZ through information sharing and input into policy and biosecurity operations.  

Research projects

Key science collaborators

  • Department of Conservation.
  • Prof Hulme, Lincoln University.
  • Landcare Research.
  • Dr Richardson, North Carolina State University, USA.
  • Dr Tobias Bickel, Department of Agriculture and Fisheries, Queensland.
  • Mr Gray Turnage, Geosystems Research Institute, Mississippi State University, USA.
  • Dr Dugdale, Agriculture Victoria, Australia.
  • Dr Getsinger, US Army Corps of Engineers, Research and Development Center, Mississippi, USA.
  • Dr Madsen, USDA ARS, Davis California, USA.
  • Dr Gross, Université de Lorraine, France.
  • Dr Hussner, Institute für Biochemie der Pflanzen, Heinrich-Heine University Dusseldorf, Germany.
  • Dr Hilt, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.

Recent publications 

See a list of our recent publications


placeholder image
Principal Scientist - Freshwater Fish
Principal Scientist - Freshwater Ecology
Principal Scientist - Freshwater Ecology
placeholder image
Freshwater Ecologist
placeholder image
Freshwater Biologist
placeholder image
Freshwater Ecologist
SCUBA diver surveying the aquatic plant community (credit: John Clayton)