Aquatic systems are under threat due to the introduction of invasive exotic species such as water weeds. Modelling work by NIWA has provided new information on which water bodies may be at greatest risk.
NIWA has developed a rapid, desktop model which assesses the potential impact of introducing new fish species to New Zealand. The model is customised to New Zealand's unique environment and endemic fish.
Estuaries in New Zealand are experiencing sedimentation at higher rates than before humans arrived here: this represents a loss both for land and estuary productivity. We need to better understand what has been happening so that we can predict the future and fight these losses.
Many of New Zealand's aquatic ecosystems, and their services, are in a degraded and often worsening state. NIWA is involved in research and consultation' aimed at improving the health of our freshwater systems.
Many New Zealand lakes are suffering from nutrient enrichment, causing potentially toxic blooms of blue-green algae. NIWA is testing a range of methods to manage phosphorus release from lake sediments – including sediment-capping agents.
Gathering, eating and sharing wild kai (food) has always been a very important part of Māori culture and wellbeing - this research project aimed to characterise the risks associated with consuming kai collected from rivers, lakes and coastlines.
Many of New Zealand's rivers fail to meet national guidelines for nutrient levels. NIWA has developed the Catchment Land Use & Environmental Sustainability (CLUES) estuary tool to predict the effects of land use on estuarine nutrient concentrations.
Streams play a key role in the ecosystems of New Zealand’s unique landscape. They feed and link together freshwater sources, maintain good water quality and support habitats that sustain our biodiversity.
Changes to the local environment and over harvesting have damaged shellfish populations in many estuaries. These projects examine the most effective way to restore these habitats and allow healthy populations of shellfish to return.