Marine
New Zealand’s marine environment is characterised by sandy and rocky beaches, exposed cliffs, bays, and estuaries of varying sizes; and a variety of coastal and deep-sea habitats and ecosystems. Beneath the surface are diverse seascapes and plant and animal life.
Three ecological classifications for New Zealand’s marine environment have been developed and are used for national state of the environment reporting:
- The Coastal Biogeographic Regions Classification, which is used as a framework to provide information on the coastal marine environment (waters less than 200 metres deep).
- The Marine Environment Classification (MEC), which is used as a framework for deep-water environments (waters 200 metres or more deep).
- The Demersal Fish Community Classification, which shows the geographic distribution of particular demersal fish communities.
Coastal Biogeographic Regions Classification
A biogeographic region is an area defined and classified according to visible ecological patterns and the physical characteristics of a geographic or hydrographic area. New Zealand is divided into 14 coastal biogeographic regions.
The Coastal Biogeographic Regions Classification can be used for assessing the health of the coastal marine environment, planning associated with marine protected areas, and reporting on the extent of marine reserves by ecosystem-type within the territorial sea.
Map showing the 14 Coastal Biogeographic Regions of New Zealand
Marine Environment Classification
The 2005 Marine Environment Classification (MEC) classifies New Zealand’s Exclusive Economic Zone (EEZ) into an ecosystem-based, spatial framework. The MEC uses eight physical factors (for example, depth, sea-surface temperature, seabed slope, tidal current, and annual solar radiation) to classify and map marine areas that have a similar environmental character. The marine environments can be mapped to different levels of detail, ranging from two to more than 70 marine environment groups.
Demersal Fish Community Classification
The Demersal Fish Community Classification uses an extensive set of research data about trawling to model the distribution of 122 demersal fish species (species that live near the sea floor). This includes blue cod, hake, hoki, john dory, orange roughy, snapper, and tarakihi.
This research data was used to estimate the abundance of fish in each species across New Zealand’s entire EEZ, including at sites for which trawl data was not available. These estimations enabled areas with a similar composition of species to be classified together.
The Demersal Fish Community Classification shows the geographic distribution of particular demersal fish communities, and describes their composition (the types of fish that live in the area) and the environmental conditions in which the fish occur.
More information on the Demersal Fish Community Classification is available on the Department of Conservation website.
