Freshwater biosecurity

Reducing the risk of new freshwater invasive species, minimising the impacts of these species, and developing methods for reducing or eradicating those populations.

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

Objectives and research projects

Biosecurity risks - advance risk assessment, prediction and modelling.

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.
  • Report on the current state of lakes and invasive species using NIWA’s LakeSPI tool.

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.
  • Develop tools to support in-lake restoration through NIWA’s Native freshwater and saltwater plant cultivation booklets and its ongoing research into aquatic plants, including the "rototurf" project which shows how native aquatic plants can be life rafts for degraded lakes. The project is a Smart Idea funded by the Ministry of Business, Innovation and Employment (MBIE).

Biosecurity exchange – a collaborative approach with stakeholders.

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

John Clayton
SCUBA diver surveying the aquatic plant community (credit: John Clayton)
Freshwater invasive species of New Zealand 2020 publication cover. [NIWA]