The marine domain begins at the mean high-water mark on the seashore and extends to the outer limits of New Zealand's exclusive economic zone, including our continental shelf.
Our marine environment supports a wide diversity of plants and animals, some of which are important food sources. It has long played an important role in Māori life, well-being, and economic systems. Our coastal waters are popular for recreational activities, while our oceans and seabed support fishing, oil and gas extraction, mineral exploration, shipping, and tourism.
Find out about the state of our marine environment, the pressures that contribute to this state, and the impact it has on us.
See Marine domain updates for the latest news on marine domain indicators.
The marine trophic index measures the changing abundance and diversity of demersal fish species (living and feeding on or near the seabed) in fishery catches. The Chatham Rise has more than 180 species of fish.
Phytoplankton are primary producers of biomass and form the basis of the oceans’ food chains. They use a pigment called chlorophyll-a (chl-a) to create their own food through photosynthesis.
Ocean acidification, measured by the reduction in sea water pH, is mainly caused by oceans absorbing and storing carbon dioxide from the atmosphere. Ocean acidification affects marine species in various ways.
Coastal sea-surface temperature is influenced by solar heating and cooling, latitude, and local geography. It is hard for some marine species to survive when the sea temperature changes. This can affect marine ecosystems and processes.
Sea-level rise is a consequence of climate change. Increases in global temperature cause ocean waters to expand, and glaciers and ice sheets to melt into oceans. Sea-level rise affects estuaries, coastal wetlands, and tidal habitats and species.
Extreme wave events can damage marine ecosystems and affect coastal infrastructure, ocean-based industries, and other human activities.
The ocean storm index estimates the number of days in a year when wind speeds exceed gale and storm force on the Beaufort Scale. In a storm, waves can be over 10 metres high.
Seabirds are one of the protected species most directly affected by fisheries in New Zealand waters. Estimating seabird deaths from bycatch is one way of assessing the pressure some seabird species face from current fishing practices.
Sea lions and fur seals are one of the protected species most directly affected by fisheries in New Zealand waters. Estimating the bycatch of sea lions and fur seals indicates the pressures they face from current fishing practices.
The Hector’s and Māui dolphins are endemic to New Zealand. Reporting the bycatch of protected species helps us understand the pressures our protected marine species face from fishing.
The bycatch, or unintended catch, of marine species other than the target species puts pressure on marine species’ populations by removing individuals or potentially modifying ecosystems.
New Zealand has 92 seabird and 14 shorebird species and subspecies (taxa) – the highest number of endemic seabirds (found only in a particular area) in the world. Decreasing bird populations can signal the ecosystem is degrading.
New Zealand has a diverse range of marine mammal species. Marine mammals are indicator species for the state of our marine environment.
Marine mammals, seabirds, and shorebirds are indicator species for the state of our marine environment. A decreasing population can indicate that the ecosystem is degrading.
Our fish stocks are affected by commercial, customary, and recreational fishing, and environmental pressures (eg ocean temperature, acidity, and productivity).
New Zealand waters have at least 117 species of chondrichthyans (sharks, rays, and other cartilaginous fish species).
Seabed trawling is the practice of towing fishing nets near or along the ocean floor. The towing process can physically damage seabed (benthic) habitats and species.
Seabed trawling, when fishing nets are towed near and along the ocean floor, can physically damage seabed (benthic) habitats and species.
Extraction processes, ship strikes, collisions with structures, disorientation from lights, and acoustic surveying can affect marine species and habitats.
The marine economy shows the contribution marine-based economic activities make to the New Zealand economy as measured by gross domestic product (GDP).
New Zealand has a diverse coastline that is 15,000km long. Reporting on our coastal seabed habitats helps us understand the state of the marine environment.
New Zealand has a marine area of more than 4 million km2. Reporting on the different environments within our marine waters helps us understand the overall state of the marine domain.
New Zealand’s 4 million km2 marine environment is diverse, with a range of coastal habitats and offshore seabed environments.
The potential impact of non-indigenous species on our native habitats and species means they could threaten our cultural and natural heritage, as well as economic activities such as commercial and recreational fishing.
Human activities can harm marine habitats. These activities can affect habitats directly (eg seabed trawling) or indirectly (eg sediment or contaminant run-off from farm land or cities). Threats can be local (eg sedimentation in an estuary) or global (eg carbon dioxide emissions driving ocean acidification).
Marine debris is a global issue with adverse effects for marine and coastal environments.
Heavy metals occur naturally in estuaries, but high concentrations suggest contamination from another source. The metals can be transported along waterways from urban environments and accumulate in estuarine and coastal sediments.
Coastal and estuarine ecosystems are affected by changes in the levels of nutrients, oxygen, and light. An overload of nutrients can be toxic or lead to algal blooms. These blooms can kill marine life by depleting oxygen levels.