| Aldermen Islands | |
| Location: | Mercury Bay in the North Island |
| Coordinates: | -36.9667°N 181°W |
| Area Km2: | 1.3 |
| Population: | 0 |
| Country: | New Zealand |
The Aldermen Islands are a small group of rocky islets to the southeast of Mercury Bay in the North Island of New Zealand. They are located off the coast of the Coromandel Peninsula, 20km (10miles) east of the mouth of the Tairua River.
The islands were named 'the Court of Aldermen' by Captain Cook and his crew on 3 November 1769 after previously naming Mayor Island.[1] The Aldermen group consists of four main islands: Hongiora, Middle, Ruamahuanui, and Ruamahuaiti. The smaller islands include Big Hump, Little Hump, Nga Horo Island, Half Island and The Spire. Their combined area is 133.5ha.[2] The islands are a forested nature reserve hosting rare species including the tuatara. Access is by permit only.
The Aldermen Islands are the remains of eroded Pliocene or Early Pleistocene lava domes that form part of the Whitianga Group.[3] Approximately 18,000 years ago during the Last Glacial Maximum when sea levels were over 100 metres lower than present day levels, the islands were hilly features surrounded by a vast coastal plain. Sea levels began to rise 7,000 years ago, after which the islands separated from the rest of New Zealand.[4] When sea levels were lower, the Tairua River flowed south of the features, travelling eastwards towards the Pacific Ocean.[4]
The scholarly investigation into the evidence of past Maori occupation on the Aldermen Islands is thoroughly documented by Moore.[5] This research integrates insights from a variety of historical accounts and field observations reported by different authors.
During the initial exploration of the Aldermen Islands, early observers such as Sladden and Falla,[6] [7] and Cochrane[8] failed to identify visible signs of previous Maori habitation. However, the investigations conducted by Bell et al. during the years 1951-58 unveiled intriguing indications on both Ruamahuanui and Middle Island. Captain Cook's historical report from 1769[9] attested to the islands being inhabited, and Wade's observations in 1842,[10] during a temporary sojourn on Ruamahuaiti, noted remnants of huts and an abundance of wild cabbage near Tuatara Bay.
The detailed description of the islands became available following the visit by Sladden and Falla (cit. opt.), and Cochrane's subsequent visit in 1959 concluded that the vegetation appeared to be "culturally unmodified." Nevertheless, earlier reports by Bell et al.[11] and Falla[12] hinted at evidence of firing on at least some of the islands.The islands are home to a substantial population of Pterodroma macroptera (grey-faced petrel) and Sphenodon punctatus (tuatara), both known for constructing burrows. The combined impact of intensive burrowing, particularly evident in areas like Hongiora, along with controlled burning, is presumed to have played a pivotal role in effacing traces of an earlier Maori population.
A crucial component of this investigation includes archaeological site descriptions compiled during the Auckland University Field Club scientific camp in May 1972. Although these descriptions and accompanying sketch maps are concise due to time constraints and limited equipment, there remains a distinct possibility that additional sites exist on the islands.
A singular recorded site (N45/1, refer to the figure in the article) aligns with Blackburn's observation in 1958. This site features a small terrace, approximately 12 m by 6 m, situated 10 m above the beach, with stone walls on two sides. Evidence of shell midden is scattered across the terrace and extends higher up the gully.
Three recorded sites include N45/2, positioned on a southward-sloping ridge over 40 m above steep cliffs. Access to this site is possible via a steep gully or a narrow, treacherous ridge. Obsidian, shell, and fish bones were found scattered in the area. N45/3, a small terrace 5–6 m above the beach, reveals concentrations of shell midden. N45/4, the largest and most intriguing site, features stone retaining walls and terraces, suggesting potential use for cultivation.
Prominent terracing on this island (N45/5) consists of nine major levels located on the most northern ridge. This site reveals evidence of shell, fish bones, obsidian, and artifacts, indicating possible Archaic Maori occupation.
While no specific sites were recorded, two obsidian flakes were collected near a freshwater spring. The discussion incorporates evidence related to stonework, pits, shell middens, and vegetation on the islands. The proximity to Mayor Is., a significant source of obsidian, raises the possibility of the islands being used for temporary shelter or visitation by coastal-traveling parties. Moreover, historical accounts suggest frequent visits by mutton-birding parties, underscoring the islands' importance as a food source for early Maoris in the region.