On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

Freshwater fish

NIWA research and tools support the protection, restoration and management of New Zealand’s freshwater fish species and the habitats that sustain them.

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    Fish Passage

    Understanding and supporting the migration of fish through New Zealand's freshwater habitats
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    Fish Passage Assessment Tool

    Software Tool/Resource
    An easy-to-use system for recording instream structures and assessing their likely impact on fish movements and river connectivity.
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    New Zealand Fish Passage Guidelines

    Recommended standards for the design and restoration of instream infrastructure to provide for fish passage
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    Fish Passage Barrier Assessment Reporting Tool (BART)

    Software Tool/Resource
    An interactive webtool to support barrier prioritisation and fish passage environmental reporting. 
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    Guidelines for monitoring fish passage success

    A manual detailing evidence-based methods suitable for evaluating the effectiveness of fish passage solutions.
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    The Bio-Acoustic Fish Fence

    Research Project
    Investigating the effectiveness of an acoustic bubble-screen in minimising the movement of pest fish
  • A 3D Printer is helping save New Zealand’s endangered native fish

    Media release
    A 3D Printer is helping save New Zealand’s endangered native fish
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    NZ Freshwater Fish Database

    Software Tool/Resource
    The New Zealand Freshwater Fish Database (NZFFD) contains over 50,000 freshwater fish observations from across New Zealand from 1901 to the present.
  • NIWA’s freshwater ecologists helping regional councils remove the barriers to fish migration

    News article
    About 76 per cent of indigenous freshwater fish species, that’s 39 out of 54, are threatened with extinction or at risk of becoming threatened.
  • Half of NZ’s rivers blocked for migratory fish

    Media release
    Nearly half of New Zealand’s river network is partially or fully inaccessible to migratory fish, a new study shows.
  • How to farm fish on land

    Dr Alvin Setiawan talks about recirculating aquaculture systems.
  • Freshwater species show vulnerability to climate change

    Media release
    A new study has identified seven freshwater species native to Aotearoa-New Zealand that will likely be highly or very highly vulnerable to climate change.