Marine Data

New Zealand has a diverse range of marine mammal species and subspecies, including whales, dolphins, seals, and sea lions. Marine mammals are indicator species for the state of our marine environment. The conservation status of a species relates to its risk of extinction.
Many of these species are endemic (only found in) to New Zealand. They are apex species (near the top of the food chain) and can thrive only if their ecosystems are healthy. A decreasing population can indicate that the ecosystem is degrading. Marine mammals played an important part in New Zealand history; in the past whales and seals were hunted in great numbers. Now we have a rapidly-growing whale- and dolphin-watching industry.

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. It can also affect fish-farming industries based in our coastal areas.
This dataset relates to the "Coastal sea-surface temperature" measure on the Environmental Indicators, Te taiao Aotearoa website.

New Zealand has a diverse coastline, which spans 15,000 km. Reporting on our coastal seabed (benthic) habitats provides important contextual information on the state of the marine domain.
This dataset relates to the "Coastal habitats" measure on the Environmental Indicators, Te taiao Aotearoa website.

These data provide a snap shot of beach litter surveys submitted by Citizen Scientist ‘Monitoring Groups’ up to April, 2019. As defined by the United Nations Environment Programme (UNEP, 2009), marine litter is any persistent, manufactured or processed solid material discarded, disposed of, abandoned or lost in the marine and coastal environment. Marine litter washed onto beaches is one of the most obvious signs of marine pollution, and can have either land or sea-based origins. Land-based sources of marine litter include input from rivers, sewage and storm water outflows, tourism and recreation, illegal dumping, and waste disposal sites. Sea-based sources include commercial shipping, fisheries and aquaculture activities, recreational boating and offshore installations.

UNEP, 2009. Marine Litter: A Global Challenge. Nairobi: UNEP. 232 pp.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Extreme wave events can damage marine ecosystems and affect coastal infrastructure, ocean-based industries, and other human activities.

Changing wave characteristics can have impacts on natural systems, as most coastal and near-shore biological communities can be damaged or destroyed by extreme wave action (Ummenhofer & Mehl, 2017). In another example, extreme waves can disrupt ferries such as those crossing the Cook Strait. Sailings are often cancelled when significant wave heights exceed six metres.

It is important to report on extreme waves to gain greater insight into their frequency, particularly as sea level and storm surges are projected to increase and can compound wave effects.

In this dataset, an extreme wave event is defined as a continuous 12-hour period during which the significant wave height equals or exceeds one of three height thresholds: four, six, or eight metres.

Four-metre-tall waves are considered extreme in the northern-most parts but are more common in the south. For the southern-most parts of New Zealand, eight-metre waves better represent extreme wave events.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

New Zealand waters have at least 117 species of chondrichthyans (sharks, rays, and other cartilaginous fish species). They are particularly vulnerable to overfishing because they are long-lived, mature slowly, and have a low reproductive rate. Chondrichthyans are important for healthy ocean ecosystems, and reporting their commercial catch and bycatch helps us understand the sustainability of our fisheries.

Phytoplankton are primary producers and form the basis of the oceans’ food chains. They contain the pigment chlorophyll-a (chl-a), which they use to create their own food through photosynthesis. We study concentrations of chl-a in phytoplankton to assess primary productivity in our oceans. Changes in productivity are likely to affect food chains and ultimately affect marine biodiversity, including the species we rely on for economic, cultural, or recreational purposes.
This dataset relates to the "Primary productivity" measure on the Environmental Indicators, Te taiao Aotearoa website.

The pH of New Zealand subantarctic waters is calculated from pCO2 (dissolved carbon dioxide) and alkalinity measurements using refitted Mehrbach constants (see Mehrbach et al, 1973; Dickson & Millero, 1987), and in-situ temperature taken from the Munida time-series transect off the Otago coast. Measurements of pCO2 are taken every two months.
The Munida transect, in the subantarctic waters off Otago, is the Southern Hemisphere’s longest-running record of pH measurements (NIWA, 2015).
More information on this dataset and how it relates to our Environmental reporting indicators and topics can be found in the attached data quality pdf.

This indicator measures the rise in annual mean coastal sea level relative to land. The national mean is derived from four long-term monitoring locations across New Zealand: Auckland, Wellington, Dunedin and Lyttelton. We also report the trends over time, from the beginning of our records until 2018. Relative sea-level rise includes the vertical land movement of the surrounding area (for example, a sinking landmass increases the rise in ocean sea level).

We report the change in annual mean coastal sea level to 2018 against the established baseline (mean sea level for 1986–2005) for the long-term sites plus an additional two sites: Moturiki (Mount Maunganui) and New Plymouth. These are not included in the national mean due to shorter records. We also measure the national annual sea-level rise for two time periods: the start of the records to 1960, and 1961–2018.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

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 intertidal and sub-tidal habitats and species. The increased likelihood of coastal erosion from sea-level rise presents a risk for seaside communities and their infrastructure, and for the marine environment itself, from increased suspended sediments.
This dataset relates to the "Coastal sea-level rise" measure on the Environmental Indicators, Te taiao Aotearoa website.