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About freshwater pests and diseases

Managing and preventing the spread of invasive freshwater weeds, pests, and diseases is important to protect our native species and local economies.

Freshwater weeds and pests can have significant impacts on:

  • commercial fisheries
  • water intakes for irrigation and hydropower generation
  • drinking water
  • recreation and tourism
  • loss of native species
  • water management costs.

What we're doing about them

We're working with organisations like regional councils, the Department of Conservation Te Papa Atawhai (DOC), Fish & Game New Zealand, Toitū te Whenua Land Information New Zealand, iwi, the National Institute of Water and Atmospheric Research (NIWA), and energy companies to prevent the spread of freshwater pests and diseases.

Through the National Interest Pest Responses (NIPR), we're trying to eradicate highly invasive freshwater pest plants like hydrilla, salvinia, water hyacinth, and phragmites.

Find out about the 9 harmful weeds managed by NIPR programmes

Find out about freshwater pests – DOC

How to report

Report exotic freshwater pests and diseases to the Biosecurity New Zealand hotline 0800 80 99 66 or online at report.mpi.govt.nz

Report regionally managed freshwater pests and diseases to your regional council.

Didymo samples hub

Find out the known or suspected locations of didymo in New Zealand

The 'Didymo Samples Hub' is an interactive map. It shows the results of sampling to determine the presence of didymo throughout New Zealand. Regional organisations do the sampling as part of their surveillance and monitoring work. Each sample is tested in a laboratory to determine the presence of didymo at a sampling site.

The Didymo Samples Hub

Note that it is possible that didymo could be present at a site that doesn't have a "positive" site status. This is because didymo could have entered the waterway since it was last sampled – so it is always best to 'Check Clean Dry' when moving between waterways.

If you are involved in didymo sampling and want to add data to the hub, email aquabiosecurity@mpi.govt.nz

 

Possession of invasive freshwater species

You need to apply for permission to possess or knowingly move freshwater species.

For some species, like carp, various aspects are managed by different organisations and you will need to contact more than one organisation for these. 

You'll need to get in touch with:

Freshwater Biosecurity Partnership Programme

The Didymo long-term management plan was established in 2007. In 2016 the plan was formally renamed to the Freshwater Biosecurity Partnership Programme incorporating all freshwater pests.

The programme works to understand and manage regional and national pathways through which significant freshwater pests are spread. This is a partnership programme and is focused on building effective relationships, increasing knowledge about the issues, best practice for management, sharing expertise, and leading the Check, Clean, Dry campaign.

Check, Clean, Dry

The Check, Clean, Dry campaign encourages recreational users of rivers and lakes to check, clean and dry their equipment (including items like wetsuits) and vehicles when moving between waterways to prevent accidental spread of weeds and pests.

Check, Clean, Dry

Who to contact

If you'd like to learn more about freshwater pests and diseases, email aquabiosecurity@mpi.govt.nz

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