Towards a Tasman Sea ocean sanctuary

The high seas are international waters outside of national jurisdictions – so the waters that do not fall within the governance of any individual country.

The responsibility for protecting the high seas is outside any single state’s jurisdiction, but the Global Ocean Treaty, brought into force in early 2026, will allow for areas of the high seas like the Lord Howe Rise and South Tasman Sea region to be protected – if governments act with the future in mind, and not the short term profits of a few powerful industries.

To create a large-scale ocean sanctuary in the Tasman Sea, countries must create a proposal and submit this to the future Ocean Treaty Conference of Parties (CoP).

The areas we are looking to protect under the high seas treaty are in international waters, parts of the Lord Howe Rise and Tasman Sea are already recognised as ‘Ecologically and Biologically Significant Areas’ (EBSAs), demonstrating just how important this region is for wildlife.

A marine protected area is a tool for protecting parts of the ocean. It can take many forms depending on how the legislation is written. Until the Global Ocean Treaty entered into force, there was no global mechanism for creating MPAs in international waters (which cover the vast majority of the  ocean). Greenpeace is campaigning for marine sanctuaries with the highest protection in these high seas areas.

There are four Levels of Protection in the MPA Guide which Greenpeace aligns with:

Fully Protected: No impact from extractive or destructive activities is allowed, and all abatable impacts are minimized.

Highly Protected: Only light extractive activities are allowed that have low total impact, and all other abatable impacts are minimized.

Lightly Protected: Some protection of biodiversity exists, but extractive or destructive activities that can have moderate to significant impact are allowed.

Minimally Protected: Extensive extraction and other activities with high total impact are allowed, but the site can still be considered an MPA under the IUCN protected area definition and provides some conservation benefit.

Seamounts are underwater knolls, hills or mountains that rise hundreds or even thousands of feet from the ocean floor. Primarily formed by volcanic activity, they can be found in ocean basins around the world. In the South Pacific, we have more than most.

These mountains rising from the deep  create the perfect  habitats for coral and sponge gardens to grow and thrive, which are then relied upon by a huge array of ocean life including   crustaceans, fish, and marine mammals.

Seamounts attract many migratory species such as tuna, sharks, sea turtles, and whales. Humpbacks are known to use seamounts in the South Pacific as way points on long journeys. Despite their global presence, less than 0.1% of the world’s seamounts have been studied.

The South Tasman Sea and Lord Howe Rise are two linked sites in the South Pacific, located between Aotearoa and Australia. 

The South Tasman Sea consists of a deep abyssal plain with steep-sided seamounts that reach almost to the surface, and Lord Howe Rise is another complex chain of seamounts leading to a vast plateau to the north.

Lord Howe Rise is an underwater plateau and part of the submerged continent of Zealandia, a volcanic lost world running through parts of the Coral Sea, down to the Tasman Sea.

The South Tasman Sea is to the south west of Lord Howe Rise and is characterized by very high densities of seabirds, and foraging areas for numerous breeding and non-breeding birds. It also has seven seamounts within it which create thriving hotspots for marine life.

This site is an Ecologically and Biologically Sensitive Marine Areas as defined under the United Nations’ Convention on Biological Diversity. It is also among the High Seas Alliance’s recommendations for the first protected areas under the new Treaty.

The Lord Howe Rise and South Tasman Sea section in the report “30×30: From Global Ocean Treaty to Protection at Sea” has more information on the importance of the region.

There are many creatures, great and small, that call these regions home including:

• Acorn worms
• Sea pens
• Shrimp
• Tuna, including bigeye tuna and Southern bluefin tuna
• Swordfish
• Sharks
• Humpback whales
• Southern right whales
• A high diversity of fish species, including orange roughy, oreos, alfonsino and bluenose
• Some of the highest density of seabirds in the world, including 14 albatross and 6 petrel species

In 2023, Greenpeace published the report 30×30: From Global Ocean Treaty to Protection at Sea which outlines three key sites which are strong candidates for protection under the Global Ocean Treaty: Emperor Seamounts of the North Pacific, Sargasso Sea in the North Atlantic, and Lord Howe Rise/South Tasman Sea in the South Pacific.

These sites all are Ecologically and Biologically Sensitive Marine Areas (EBSAs) as defined under the United Nations’ Convention on Biological Diversity. They also are among the High Seas Alliance’s recommendations for the first protected areas under the new Treaty, because of how biodiverse they are, and progress towards protection in each is politically mature enough to make them prime contenders to be among the first ocean sanctuaries created using the Treaty.

These are not the only potential ocean sanctuary sites we will work on in the coming years, but we use them as case studies in this report to help illustrate the pathway to protection for ecologically important marine areas that could realistically be protected soon after the Treaty has been ratified.

We are calling on the New Zealand Government to ratify the Global Ocean Treaty and back the creation of an ocean sanctuary in the Tasman Sea.