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

Algae

NIWA operates specialises in the analysis of cyanobacteria and other algae, including algal counts and toxin testing, to find out whether an algal bloom is potentially toxic.

  • Putting algae to work

    Feature story
    Can native freshwater algae help restore the mauri of local waterways? Lawrence Gullery investigates.
  • Scientists listen to the sound of photosynthesising seaweeds

    Media release
    NIWA scientists are hoping they may one day be able to “listen” to kelp forests in the waters around New Zealand to find out how they are faring.
  • From small beginnings a valuable collection grows

    Media release
    Cathy Kilroy is quick to admit she’s a person who doesn’t like throwing anything away.
  • algal bloom

    Algal monitoring service

    Service
    Blooms of hazardous cyanobacteria (blue-green algae) in rivers, lakes and reservoirs can cause problems for both animal and human health.
  • (no image provided)

    Coralline Algae

    This identification guide covers the common crustose coralline algae found in central New Zealand.
  • (no image provided)

    Algae ID guides

    A collection of ID guides to algae. Groups include major freshwater algal groups, diatoms and blue-green (cyanobacteria), red and green algae.
  • Q&A - Bloomin' algae!

    Feature story
    A hot and steamy summer saw Kiwis heading down to rivers and lakes to cool off. But they weren’t the only ones enjoying the warmer weather – algae had a great time too.
  • Geomorphology influences periphyton abundance

    Research Project
    This research project investigated whether the mechanisms for periphyton removal in rivers relate more directly to hydraulic and geomorphic conditions than flow metrics.
  • Beautiful Browns

    News article
    Do you know where in New Zealand to find Neptune’s necklace or rimurapa? Or how to tell apart Carpophyllum from Cystophora?
  • Reclassifying karengo (nori)

    Research Project
    The seaweed known colloquially as nori in Japanese - used for making sushi - or karengo in Maori has been reclassified by an international team of scientists including NIWA's Dr Wendy Nelson.
  • Specialist analytical services

    Service
    Find out more about our specialist analytical services.
  • Bio-oil from wastewater algae

    Research Project
    This project will demonstrate the commercial feasibility of producing bio-oil by the conversion of algae biomass that has been grown in wastewater treatment facilities. In particular we aim to maximise algae production in High Rate Algal Ponds (HRAP) by adding carbon dioxide, and demonstrate energy efficient conversion of algal biomass to bio-oil.