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1 Introduction

What is the Exclusive Economic Zone?

1.1 New Zealand’s Exclusive Economic Zone (EEZ) is the area of sea and seabed that extends from 12 to 200 nautical miles offshore. It is the fifth largest EEZ (approximately 430 million hectares) in the world, about 15 times the size of our land mass.

1.2 New Zealand has lodged with the United Nations a submission defining the limits of our Extended Continental Shelf. The proposals in this paper may, as far as possible under international law, also be applicable to this area.

Figure 2: New Zealand’s Exclusive Economic Zone

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1.3 New Zealand has full sovereignty over the territorial sea out to 12 nautical miles. The proposals in this paper do not cover this area.

Environmental, economic and cultural values

1.4 New Zealand’s marine ecosystems and species are highly diverse. Habitats in the EEZ range from plains of mud to volcanic vents in seamounts of the deep ocean, where micro-organisms “breathe” sulphur rather than oxygen. New Zealand is visited by a number of migratory species and provides habitats that are critical to the long term viability of some of these species, particularly marine birds that breed in New Zealand.

1.5 Marine scientists estimate that a high proportion of New Zealand’s indigenous biodiversity is found in the sea. Although many of our fish species are found elsewhere in the world, many of our benthic (bottom-dwelling) marine species are found only in New Zealand waters. Evaluating the state of New Zealand’s EEZ marine biodiversity is difficult due to the very limited information we have about deep-sea species. We know far more about the nearshore marine environment.

1.6 New Zealand’s EEZ also provides us with considerable economic opportunities. Fishing is a major export earner. However, despite the size of New Zealand’s EEZ, the productivity of our fisheries is relatively low because the waters are deep (New Zealand’s offshore fisheries are among the deepest in the world) and not particularly rich in nutrients.

1.7 Oil and gas have been discovered in several parts of New Zealand’s offshore territory, although the only commercial production has been through the development of the Maui gas field, extending 35 to 50km off the Taranaki coast. Three Taranaki basin oil and gas fields are currently under commercial development in the EEZ (Kupe, Tui and Maari). With the increase in oil and gas prices as well as the decline in the Maui gas field, oil and gas exploration has increased in New Zealand’s EEZ. A number of offshore oil and gas fields are being appraised and may be developed over the next few years. For example, there is high interest in oil and gas exploration in the Great South Basin, offshore Taranaki, and off the east coast of both the North and South Islands.

1.8 The EEZ connects us to the rest of the world through shipping and undersea telecommunication cables. Almost 85% of New Zealand exports by value (99% by volume) are carried by sea, and around 90% of international telecommunication services within New Zealand are carried on submarine cable systems. A submarine cable failure would have a serious impact on the New Zealand economy.

1.9 The ocean offers great potential for innovation and investment in a range of different wealth-creating activities. Although much of New Zealand’s land-based resources and fisheries are already being utilised, the EEZ and continental shelf offer significant untapped space and resources for future developments.

1.10 There has been recent interest in exploration for seabed minerals, such as “seafloor massive sulphides” deposits on the Kermadec Ridge and gold off the west coast of the South Island. Methane hydrates may also generate interest if proven to be commercially viable. Biological prospectors search marine life for new and valuable chemical compounds.

1.11 In the future, new and innovative activities may be developed, such as new types of minerals exploration, marine energy generation, deep-sea aquaculture, or carbon capture and sequestration. These new kinds of activity face high cost and technological barriers.

1.12 The proposals in this paper focus on regulating environmental effects, but they also recognise cultural values. Maori have a close cultural relationship with the ocean, particularly inside the territorial sea. Some iwi have cultural connections with specific areas in the EEZ; for example, the Kermadec Ridge has special significance for Tuwharetoa, as it played an important role in their ancestral migrations to Aotearoa.

1.13 Management of shipwreck sites in the EEZ might also become of increased importance as technology allows deeper sites to be reached.

Status of the EEZ under international law

1.14 Under the United Nations Convention on the Law of the Sea, New Zealand has full sovereignty in the territorial sea, largely equivalent to that over the land. New Zealand has a more limited set of “sovereign rights” in the EEZ. These rights are for the purpose of exploring, exploiting, conserving and managing the living and non-living resources of the EEZ, as well as in relation to other activities for the economic exploitation and exploration of the zone, such as the production of energy from the water, current and winds.

1.15 New Zealand also has jurisdiction in relation to artificial islands, installations and structures, marine scientific research, and the protection and preservation of the marine environment.

1.16 Sovereign rights are subject to various conditions and obligations, such as international controls on marine transport and pollution, the right of any state to lay submarine pipelines and cables, and freedom of navigation.

1.17 New Zealand also has sovereign rights for exploring and exploiting the natural resources of the continental shelf, including where it extends beyond the EEZ. New Zealand has lodged with the United Nations a submission defining the limits of our Extended Continental Shelf. As far as possible under international law, an improved EEZ regulatory regime for environmental effects could also apply to the Extended Continental Shelf seabed and subsoil resources (e.g. minerals).

1.18 Much of our existing legislation relating to the EEZ flows directly from international agreements. For example, rules under the Maritime Transport Act 1994 directly implement New Zealand’s obligations under the London Dumping and MARPOL1 conventions. Regulation that is developed for the EEZ needs to be consistent with international law. We cannot assume the options are the same as those available under New Zealand’s sovereignty in the territorial sea.


1 International Convention for the Prevention of Pollution from Ships