Estuaries

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Latest news

The future shape of water

11 February 2021

How much is too much? Susan Pepperell looks at some of the tough decisions looming around access to freshwater and how science is helping with solutions.

Freshwater species show vulnerability to climate change

Media Release

15 September 2020

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.

Mangroves: to clear or not to clear?

Media Release

19 May 2017

NIWA scientists have written a guide for managing mangroves, prompted by a desire for people to learn more about mangrove ecosystems, and what happens when they are removed.

Paradise for eels? Getting to know the secrets of NZ's new icon

Feature story

9 May 2017

As New Zealand's "Mr Eel", Niwa's Dr Don Jellyman has heard every tall tale. And some of them may be true.

Our work

Maniapoto Cultural Assessment Framework

Maniapoto Māori Trust Board and NIWA worked collaboratively during 2018-19 to support Ngāti Maniapoto whānau to reconnect with and participate in the assessment of their freshwater according to their values.

Changes in juvenile fish habitats

NIWA is looking for people who have had a long association with the Hauraki Gulf or Marlborough Sounds to help them with a research project on juvenile fish habitats.

Predicting long-term sedimentation and heavy metal accumulation in estuaries

NIWA has developed an Urban Stormwater Contaminant (USC) model to enable urban planners to predict sedimentation and heavy metal accumulation in estuaries and identify problem areas in order to target mitigation measures.

The New Zealand Estuary Trophic Index

Excessive nutrient input (eutrophication) threatens many New Zealand estuaries causing ecological problems, such as algal blooms and poor physical and chemical conditions for estuarine life.

Latest videos

The world's most mysterious fish

A video about The world's most mysterious fish. NIWA researchers are working with iwi to try to unlock the secrets of New Zealand tuna—freshwater eels. Every year tiny, glass eels wash in on the tide at river mouths along our coast. But where do they come from and how do they get there?

Ngā Waihotanga Iho - The Estuary Monitoring Toolkit

The main purpose of Ngā Waihotanga Iho is to provide tools for the public to measure environmental changes that occur in estuaries over time.

Restoration of aquatic ecosystems

This project aims to increase our knowledge of aquatic ecosystems and their restoration, and apply this to degraded streams, rivers, lakes and estuaries.

The future shape of water

Feature story

11 February 2021

How much is too much? Susan Pepperell looks at some of the tough decisions looming around access to freshwater and how science is helping with solutions.

Eutrophication Explorer

A web application tool to explore monitoring data and model predictions related to stream and estuary eutrophication

New freshwater species programme

A new programme at NIWA will focus on finding ways to protect our freshwater species now and in the future.

Staff profile: Dr Simon Woodward

In this edition we welcome Dr Simon Woodward to the team and find out how he came to work at NIWA.

Freshwater species show vulnerability to climate change

Media Release

15 September 2020

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.

Maniapoto Cultural Assessment Framework

Maniapoto Māori Trust Board and NIWA worked collaboratively during 2018-19 to support Ngāti Maniapoto whānau to reconnect with and participate in the assessment of their freshwater according to their values.

Climate Change Vulnerability Assessment (CCVA)

To prepare for changes in climate, our freshwater and oceans decision-makers need information on species vulnerability to climate change.

From land to sea – tracing our trash

NIWA and the Sustainable Coastlines charitable organisation are collaborating to develop ‘source-to-sea’ methods to trace the movement of litter from stormwater systems, through rivers, to coastlines.

The world's most mysterious fish

A video about The world's most mysterious fish. NIWA researchers are working with iwi to try to unlock the secrets of New Zealand tuna—freshwater eels. Every year tiny, glass eels wash in on the tide at river mouths along our coast. But where do they come from and how do they get there?

Our seas are warming

The seawater in the New Zealand region is significantly warmer than it was 30 years ago. All indications are that the warming trend will continue.

Slowing the mud invasion

New Zealand's estuaries were once sandy, forest-lined gems.

Freshwater Update 76, March 2018

Freshwater Update 76 brings you the latest information from our Freshwater & Estuaries Centre, with articles ranging from spring and river water condition to urban waters, didymo and aquatic plant scientists.

The New Zealand Estuary Trophic Index

Excessive nutrient input (eutrophication) threatens many New Zealand estuaries causing ecological problems, such as algal blooms and poor physical and chemical conditions for estuarine life.

Protecting and restoring seagrass – what have we achieved and where to next?

The extent of NZ’s seagrass meadows has declined substantially in the last 50 years. This has been most evident in estuaries strongly affected by human activities. But seagrass meadows can be restored and NZ has a local example to prove it.

Using new laser technology to measure bank erosion

Fine sediment is NZ’s most widespread contaminant, degrading ecosystems and impairing recreational, cultural and aesthetic values in our rivers, estuaries, and coastal seas.

Compound Specific Stable Isotope tracing of sediment sources - tools to manage a sticky problem in New Zealand’s freshwaters and estuaries

Fine sediment is New Zealand’s most widespread water contaminant, degrading ecosystems, infilling dams and reservoirs and impairing recreational, cultural and aesthetic values in our rivers, estuaries and coastal seas.

Mangroves: to clear or not to clear?

Media Release

19 May 2017

NIWA scientists have written a guide for managing mangroves, prompted by a desire for people to learn more about mangrove ecosystems, and what happens when they are removed.

Paradise for eels? Getting to know the secrets of NZ's new icon

Feature story

9 May 2017

As New Zealand's "Mr Eel", Niwa's Dr Don Jellyman has heard every tall tale. And some of them may be true.

Toolkit development

A number of individuals, organisations and hapū have contributed to the development of Ngā Waihotanga Iho.

Getting started

This section outlines some practical matters you need to consider before using any of the modules.

Managing mangrove expansion

This manual aims to provide the guidance needed to manage mangrove expansion, while maintaining the ecological integrity of estuaries and harbours.

Muddy sinks

Feature story

22 February 2017

New Zealand’s mangrove swamps and coastal marshes may be particularly adept at absorbing and storing the carbon we emit.

Monitoring and maintenance of kōura

Once you have identified the problem, and applied the necessary tools for restoring kōura to your stream, the next phase of your project is to monitor the site to see whether restoration works.