Oaia Island

The island is home to an Australasian gannet colony. The population increased by more than five times between 1940 and 1970 to a total of 892 breeding pairs, which had a negative effect on vascular plant life on the island.^[3] As the colony expanded, gannets began to settle at the Muriwai gannet colony to the east.^[4] The island has been classified as identified as an Important Bird Area by BirdLife International, as a part of the Muriwai and North Auckland Seabird Flyway areas.^[5][6]

Flora on the island includes Disphyma australe (New Zealand ice plant), Chenopodium allanii and Coprosma repens (taupata), with historic records indicating Lepidium oleraceum previously was found on the island.^[3] Seashore earwigs have been identified on Oaia Island, and New Zealand fur seals are known to visit the island.^[3]

The island is a habitat for the rare korowai gecko, which was first identified as living on the island in 1954; then thought to be a different species of gecko, Woodworthia maculata.^[7]

The traditional Tāmaki Māori name for the island is Motu-ō-Haea ("Brilliant White Island"), a reference to gannett and seagull guano colouring the island white.^[1][8] The island was traditionally visited by Te Kawerau ā Maki, as a place where food resources could be collected in calm weather, including birds, bird eggs, and kekeno (New Zealand fur seals).^[8]

In 1902, politician and later Mayor of Auckland City, Edwin Mitchelson, constructed a wooden mansion at Muriwai which he named Oaia, after the island.^[9]

Oaia Island is the subject of Colin McCahon's acrylic landscape Moby Dick Is Sighted Off Muriwai Beach (1972), which was featured in a New Zealand Post stamp campaign in 1997.^[9][10]