Marae Moana extends over 1.976 million square kilometres of ocean. This is the entire Cook Islands Exclusive Economic Zone which lies from 6 degrees south to 25 degrees south and 155 degrees west to 169 degrees west. The park is comprised of fifteen tropical islands with fringing coral reefs. These islands include seven atolls, four upraised coral reef islands (“makatea”), two sand cays, one almost atoll and one volcanic island. The open ocean dominates the park, with the islands making up only 237 square kilometres or 0.02% of the total area. 

Name of Island

Type of Island

Land Area (km2)

Human Population (2011)

Rarotonga Volcanic 67.1 13,095
Aitutaki Almost-atoll 18.3 2,038
Mangaia Upraised limestone 51.8 572
Atiu Upraised limestone 26.9 480
Mauke Upraised limestone 18.4 307
Mitiaro Upraised limestone 22.3 189
Palmerston Atoll 2.1 60
Manuae Atoll 6.2 0
Takutea Sand Cay 1.0 0
Pukapuka Atoll 1.3 451
Nassau Sand Cay 1.3 73
Manihiki Atoll 5.4 239
Rakahanga Atoll 4.1 77
Penrhyn Atoll 9.8 213
Suwarrow Atoll 0.4 0

 Table 1 Islands within Marae Moana, their land area and human population

Marae Moana comprises several tropical ecosystems typical of tropical island environments. Coral reefs encircle all fifteen islands and these are separated by the pelagic ecosystem. Although there is no biological data, bathymetric data indicates there are possibly seamount ecosystems within the park. A variety of tropical forest ecosystems exist on the islands. These include littoral forests, the Rarotonga montane rainforest, Rarotonga cloud forest and makatea forest on the upraised limestone islands. Wetland ecosystems include streams, swamps and lakes. Unlike most tropical island environments, there are no mangrove or seagrass ecosystems in the Cook Islands, although there is archaeological evidence that the mangrove Rhizophora sp. previously existed in Mangaia.
There are 136 identified coral species and some 650 species of fish in coral reefs of Marae Moana. Twenty two cetacean species have been observed in the open ocean. 


Common Name

Megaptera novaeangliae

Humpback whale

Balaenoptera borealis

Sei whale

Balaenoptera musculus

Blue whale

Balaenoptera bonaerensis or

Balaenoptera acutorostrata sp

Antarctic minke whale or Dwarf common minke whale

Physeter macrocephalus

Sperm whale

Orcinus orca

Killer whale

Globicephala macrorhynchus

Short-finned pilot whale

Ziphius cavirostris

Cuvier's beaked whale

Mesoplodon densirostris

Blainville's beaked whale

Peponocephala electra

Melon-headed whale

Balaenoptera edeni

Bryde’s Whale

Pseudorca crassidens

False Killer Whale

Delphinus delphis/frontalis

Common dolphin

Lagenorhynchus australis

Peale's dolphin

Stenella longirostris

Spinner dolphin

Stenella attenuate

Striped/Spotted dolphin

Lagenodelphis hosei

Fraser's dolphin

Grampus griseus

Risso's dolphin

Steno bredanensis

Rough Toothed dolphin

Tursiops truncates

Bottle-nosed dolphin

Table 2 Cetaceans found within Marae Moana (Source: Cook Islands Whale Research and Cook Islands Natural Heritage Project)

Three globally threatened marine turtle species have been identified in Marae Moana – the Green Turtle (Chelonia mydas), the Hawksbill Turtle (Eretmochelys imbricata) and the Loggerhead Turtle (Caretta caretta). The Green and Loggerhead Turtles are endangered and the Hawksbill critically endangered.

Tuna species typically identified in Marae Moana include Skipjack (Katsuwonus pelamis), Albacore (Thunnus alalunga), Yellowfin (Thunnus albacares), Bigeye (Thunnus obesus). Mackeral Tuna (Euthynnus affinis) and the Frigate Tuna (Auxis thazard). Big Eye Tuna (Thunnus obsesus) is identified as a globally threatened species with vulnerable status.

There are six reef shark species and eleven pelagic shark species found in Marae Moana.


Common Name

Nebrius ferrugineus

Carcharhinus albimarginatus

Nurse Shark

Silvertip Shark

Carcharhinus amblyrhynchos

Carcharhinus melanopterus

Triaenodon obesus

Hexanchus griseus

Rhincodon typus

Carcharhinus falciformis

Carcharhinus galapagensis

Carcharhinus longimanus

Galeocerdo cuvier

Prionace glauca

Sphyrna lewini

Alopias pelagicus

Isurus oxyrinchus

Isistius brasiliensis

Echinorhinus cookie

Grey Reef Shark

Blacktip Reef Shark

Whitetip Reef Shark

Bluntnose Sixgill Shark

Whale Shark

Silky Shark

Galapagos Shark

Oceanic Whitetip Shark

Tiger Shark

Blue Shark

Scalloped Hammerhead Shark

Pelagic Thresher Shark

Shortfin Mako Shark

Cookiecutter Shark

Prickly Shark

Table 3 Shark species found within Marae Moana

Globally Threatened Species

With the support of Birdlife International, the Critical Ecosystems Partnership Fund, and help from the Cook Islands Natural Heritage Database, an analysis of Cook Islands Key Biodiversity Areas and Important Bird Areas was performed in 2012. The southern group islands are the most studied and therefore have the most comprehensive and reliable information. Marae Moana is home to 61 globally threatened species as well as many endemic species that are threatened. There are 25 threatened coral species, 8 threatened fish species, 3 marine turtle species and 3 threatened whale species. There are also 8 threatened land bird species, 11 threatened plants, one tree snail, one skink and one threatened seabird. Threatened species in the Marine Park are listed in Table 4. 

Threatened Coral Species

Acropora anthocercis

Staghorn coral

Leptoseris incrustans

Encrusting coral

Acropora globiceps

Staghorn coral

Montipora angulata

Montipora coral

Acropora horrid

Staghorn coral

Montipora australiensis

Montipora coral

Acropora microclados

Staghorn coral

Montipora calcarea

Montipora coral

Acropora palmerae

Staghorn coral

Montipora caliculata

Montipora coral

Acropora paniculata

Staghorn coral

Montipora lobulata

Montipora coral

Acropora polystoma

Staghorn coral

Pavona bipartite

Pavona coral

Acropora retusa

Staghorn coral

Pavona cactus

Pavona coral

Acropora speciosa

Staghorn coral

Pavona decussata

Cactus coral

Acropora striata

Staghorn coral

Pocillopora elegans

Pocillopora coral

Acropora vaughani

Staghorn coral

Turbinaria mesenterina

Pagoda coral

Alveopora allingi

Alveopora coral

Turbinaria reniformis

Yellow scroll coral

Alveopora verrilliana

Alveopora coral

Threatened Fish, Turtle & Whale Species

Alopias pelagicus

Pelagic Thresher Shark

Cheilinus undulates

Humphead Wrasse

Carcharhinus longimanus

Oceanic Whitetip Shark

Thunnus obesus

Big-eye Tuna

Taeniura meyeni

Giant reef ray

Eretmochelys imbricate

Hawksbill Turtle

Isurus oxyrinchus

Shortfin Mako

Chelonia mydas

Green Turtle

Rhincodon typus

Whale shark

Caretta caretta

Loggerhead Turtle

Epinephelus lanceolatus

Giant Grouper

Balaenoptera musculus

Blue Whale

Plectropomus laevis

Black Saddled Coral Grouper

Balaenoptera borealis

Sei Whale

Physeter macrocephalus

Sperm Whale

Threatened Bird Species

Pomarea dimidiate

Rarotonga Flycatcher

Todiramphus ruficollaris

Mangaia Kingfisher

Vini kuhlii

Rimatara Lorikeet

Vini peruviana

Blue Lorikeet

Collocalia sawtelli

Atiu Swiftlet

Aplonis cinerascens

Rarotonga Starling

Ptilinopus rarotongensis

Cook Islands Fruit Dove

Numenius tahitiensis

Bristle-thighed Curlew

Pterodroma leucoptera

Gould’s Petrel

Other fauna

Partula hyaline

Polynesian Tree Snail

Emoia adspersa

Micronesian Skink

Threatened Plant Species

Acrophorus raiatensis

Rarotonga Acrophorus

Cyrtandra rarotongensis

Rarotonga Cyrtandra

Asplenium schizotrichum

Polynesian Asplenium

Garnotia cheesemanii

Rarotonga Garnotia grass

Coprosma laevigata

Rarotonga Coprosma

Haloragis stokesii

Rarotonga Haloragis

Cyrtandra lilianae

Te Manga Cyrtandra

Psychotria whistleri

Rarotonga Psychotria

Radiogrammitis cheesemanii

Cloud grass fern

Sclerotheca viridifolia

Rarotonga Sclerotheca

Nesoluma polynesicum

Polynesian Nesoluma

 Table 4: Threatened Species in Marae Moana

Seabird Populations

The uninhabited islands of Takutea and Suwarrow are home to globally significant numbers of seabirds within Marae Moana. Suwarrow supports over 100,000 seabirds and nine resident species. The atoll supports globally significant proportions of the world's Sooty Tern (Sterna fuscata), Lesser Frigatebird (Fregata ariel), and Red-Tailed Tropic Bird (Phaethon rubricauda) On Takutea, there is the Red-Tailed Tropic Bird, Brown Booby (Sula leucogaster), Masked Booby (Sula dactylatra), Red-Footed Booby (Sula sula), Great Frigatebird (Fregata minor), Brown Noddy (Anous stolidus), Black Noddy (Anous minutus) and White Tern (Gygis alba). Takutea also has globally significant populations of Red-tailed Tropic bird. 

Key Biodiversity Areas and Important Bird Areas

Key Biodiversity Areas (KBAs) and Important Bird Areas (IBAs) are places that contain significant populations of globally threatened species. There are sixteen Key Biodiversity Areas within Marae Moana, seven of these are also Important Bird Areas.

Protected Areas

Marae Moana encompasses forty-one protected areas. These protected areas include twenty-six marine areas, seven marine-terrestrial areas, five terrestrial areas, two freshwater lakes and one saltwater marsh. The Cook Islands Whale Sanctuary encompasses the entire area of Marae Moana and still requires legal designation. Marae Moana is also a Shark Sanctuary, established through the Marine Resources (Shark Conservation) Regulations 2012. It is intended to assist communities with either the formal establishment or improved management of protected areas throughout Marae Moana.