Biodiversity

The Kermadec region has never been connected to the mainland. Because of its isolation, it has developed unique biodiversity, above and below the water. A special feature of the inshore waters is the abundance of large predatory fish, lik:

• Galapagos sharks
• spotted black grouper (which can grow to about 2 meters here)
• kingfish.

Between late August and early November, humpback whales, including mothers with calves, migrate south through the archipelago. They pass close to Raoul Island. 
 
Green turtles and other tropical marine species are common around Raoul Island. In fact, five of the world’s seven sea turtle species can be found here. Subtropical and temperate species are more common in the southern islands' waters.
 
All of the islands have breeding colonies of seabirds. The largest colonies are on the smaller islets off Raoul and Macauley Islands, which have remained rat-free since humans arrived.

Polynesian heritage

Raoul island was settled by early Polynesians between 600 and 1,000 years ago. As a result, Raoul island may hold important clues to understanding the Māori migration voyages between eastern Polynesia and Aotearoa/New Zealand. Settlement of the island appears to have been intermittent, possibly failing for want of resources or due to volcanic activity.

Evidence of occasionally extensive ancient settlements remains, mainly on the northern coast of Raoul at Low Flat, the Farm Terrace, and Coral Bay. It is likely that the Denham Bay Caldera beachfront was also occupied at times.

There is evidence of communities based on coastal fishing. This includes the harvesting of seabirds and marine mammals as well as tools production and other artefacts from local basalt and obsidian.

The Kermadec Islands have a number of plants that were probably introduced by voyagers from other parts of Polynesia. The presence of kiore, a species of rat now eradicated from Macauley Island, also indicates Polynesian contact with that island.

Māori scholars believe the Kermadec archipelago represents a place called Te Rangitahua in their oral history, particularly Raoul Island. The Aotea and Kurahaupo canoes both visited Te Rangitahua on the way from Rarotonga to Aotearoa in the fourteenth century. The Kurahaupo was damaged there, and most of the crew transferred to the Aotea to travel on to Aotearoa. The Kurahaupo was repaired and eventually landed at Takapaukura (Tom Bowling Bay) in Northland.

European heritage

Early European voyagers also based activities, particularly whaling, on the islands and much of their early eighteenth and nineteenth century contact with Aotearoa resulted from this.

From the early to mid nineteenth century, Raoul and Macauley islands were used extensively for provisioning by whaling vessels operating in the French Rock and Vasquez grounds near the Kermadec Islands.

From 1836 onwards, there were a number of European attempts to settle Raoul, focused mainly on Denham Bay and to a lesser extent at Low Flat and the Terraces. Exotic plants and animals were introduced and areas cleared for pasture and cultivation.

The New Zealand Government annexed the Kermadecs in 1887. Provision depots for shipwrecked sailors were established on the main islands in the southern Kermadecs in 1888.

In 1934 most of Raoul Island and all of the other islands in the group were set aside as a flora and fauna reserve, later to become a nature reserve. The rest of Raoul (111ha) was set aside for a meteorological station on the island in 1938, when the last independent settlers left the island. DOC acquired this block of land in 1991.

Volcanic history

The Kermadec Islands are a chain of about 80 volcanoes that stretch for 2,600 km between Tonga and New Zealand.

Deepwater volcanic vents have large beds of giant vent mussels, found only in this area. These mussels provide a habitat for deepwater crabs and a unique eel-like fish called the eelpout. Other places have fields of sea lilies (stalked crinoids), but most of the sea floor beyond the vents is bare rock and fine sediments.

The Pacific and Australasian tectonic plates meet along the Kermadec Trench. This causes the Australasian plate to lift and buckle while the Pacific plate sinks. The volcanic chain is formed when the Pacific plate melts as it goes under the Australasian plate. 

Raoul Island is the largest in the group, which starts at the southernmost island, L’Esperance. While the other islands and islets are smaller, many of them have important bird colonies.