About NIWA Lake Submerged Plant Indicators

LakeSPI (pronounced "Lake Spy") uses Submerged Plant Indicators (SPI) for assessing the ecological condition of New Zealand lakes.

You can use this website to take a closer look at a lake near you!

  • Learn more about the ecological condition of your lake.
  • Discover which submerged plants are growing in your lake.
  • Follow changes occurring in your lake over time.

The underlying principle of LakeSPI is that any New Zealand lake can be characterised by the composition of native and invasive plants growing in the lake and the depth to which they grow.

Once key submerged plant indicators have been identified and recorded using the LakeSPI survey method, LakeSPI applies a simple scoring system to generate 3 LakeSPI indices (or scores):

  • Native Condition Index — This captures the native character of vegetation in a lake based on the diversity and quality of native plant communities.
  • Invasive Impact Index — This captures the invasive character of vegetation in a lake based on the degree of impact by invasive weed species.
  • LakeSPI Index — This is a synthesis of components from both the native condition and invasive condition of a lake and provides an overall measure of the lake's ecological condition.

By using submerged plants as indicators, the effects of water quality, and the impacts of catchment management and aquatic weed invasion can be assessed. This is just one of the many uses of LakeSPI.

More Information

NIWA acknowledges the financial assistance of the Terrestrial and Freshwater Biodiversity Information System (TFBIS) Programme towards the development of this LakeSPI web reporting portal. The TFBIS Programme is funded by the Government to help to achieve the goals of the New Zealand Biodiversity Strategy, and is administered by the Department of Conservation.