Healthy marine ecosystems

Find out about the work we do to honour the Treaty of Waitangi and help to protect New Zealand marine ecosystems from the effects of fishing.

Managing today for future generations

New Zealand is home to many unique species, and has incredible marine ecosystems, ranging from shallow reefs to submarine mountains. It's home to a great number of seabird and marine mammals that are not found anywhere else in the world.

Some of these are rare, and others are endangered. We want to help protect these species and ecosystems for future generations.

Work and research for the aquatic environment and biodiversity

It's important that we consider and respond to the effects that fishing activities have on the environment. This involves research and effective decision-making.

The work and research we do for the aquatic environment and biodiversity is covered in an annual review document that we publish.

Scientific research projects that we commission to inform management action on these issues are summarised in the AEBAR. They are published through the AEBR report series and the mainstream scientific literature.

Find AEBR documents – fisheries reports and stock statistics

The Annual stock assessment plenary document summarises the status of fishstocks in the Quota Management System. Some chapters have information on:

  • bycatch of fish that were caught (that were not being targeted)
  • protected species bycatch
  • the trawl footprint.

Find the most recent plenary documents – about our fisheries research

Find out about the Quota Management System

Minimising fishing interactions with protected species

Protected wildlife are often attracted to commercial fishing boats. This means that species that fishers are not trying to catch can get caught accidentally. This is known as “bycatch”. Work we do to minimise bycatch includes:

  • regulations around fishing gear
  • devices to keep seabirds away
  • devices to release marine mammals caught in fishing nets
  • closing areas to fishing.
  • reporting of protected species catches
  • cameras and digital monitoring
  • observer coverage.

We have strategic plans that focus on protecting certain species from the effects of fishing.

Protecting seabed habitats and marine ecosystems

Bottom fishing continues to be the preferred commercial fishing method in New Zealand. However, awareness of the effects that this can have on the seabed has increased.

Since 2007, 30.2% of New Zealand's seabed has been protected against bottom fishing (dredging and bottom trawling). This covers an area 4 times the landmass of New Zealand. This was done through implementing benthic protection areas and seamount closures.

Closing areas to fishing and restricting fishing activity

As well as the seabed closures, there are marine protected areas (MPAs). These include:

  • marine reserves
  • closed and restricted fishing areas
  • customary management areas such as mātaitai reserves.

Coastal pressures: understanding the effects of run-off

Water that runs off the land can carry pollution, sediment, and nutrients (like fertiliser) into the sea. This can come from farms, rivers, roads, and urban areas. Over time, this can alter coastal ecosystems and the wider marine environment and make it less suitable for coastal shellfish and fish species. We work with other government agencies to address this.

A review of land-based effects on coastal fisheries and supporting biodiversity in New Zealand

MPI's fresh water reform programme

CARIM (Coastal Acidification: Rate, Impacts, and Management) project

Biodiversity in our oceans

Marine biodiversity refers to how many species there are in a habitat or area in the ocean. Having a large biodiversity is important and something we want to support.

We do work to understand the state and role of biodiversity in healthy marine ecosystems. This includes:

  • mapping seabed communities
  • developing biodiversity and ecosystem indicators
  • understanding multiple pressures that the marine environment is subject to.

We report on these in our Marine Biodiversity Programme. The work contributes to national and international strategies concerning marine biodiversity and sustainable fishing practices.

Changes in our oceans

Climate change is starting to affect ocean temperature, acidity levels, and currents around the world. We're still learning what these changes will mean for fisheries and marine ecosystems and are working with other government agencies on how best to respond.

Current research we do focuses on:

  • assessing how vulnerable fish and fisheries are
  • fish movements around the ocean
  • changes in fish growth and productivity
  • changes in ecosystems
  • cumulative effects
  • ecosystem scale response to climate change.

Find out more

Chapter 12 AEBAR: New Zealand climate and ocean setting [PDF, 4 MB]

Our marine environment 2019 – Ministry for the Environment

Adapting to climate change in New Zealand: Recommendations from the Climate Change Adaptation Technical Working Group – Ministry for the Environment

Moana Project

Science working groups

We have 2 science groups that are dedicated to evaluating research that we commission on the effects of fishing on the aquatic environment and biodiversity in New Zealand waters.

  • The Aquatic Environment Working Group (AEWG) commissions and evaluates research on the effects of fishing on the environment, including protected species.
  • The Biodiversity Research Advisory Group (BRAG) explores broader issues at an ecosystem scale, as well as climate change and ocean acidification.

Both science groups include:

  • fishery scientists
  • researchers from across government
  • research institutes
  • industry
  • universities
  • non-government organisations.

The AEWG and BRAG meetings also include fishery managers.

Who to contact

If you have questions about the information on this page, email

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