The cultural landscape
Parts of Ahuahu are well preserved. There are 23 pā sites. There are many Māori gardens in the north. There is evidence of kūmara storage pits and places where stone tools were made. There are also sites with shell midden and fish bone.
Toolmaking
This region has some of the most valuable stone in the North Island. On Ahuahu, archaeologists have found:
- Basalt - used to make adzes and general use tools.
- Obsidian – used for cutting and scraping.
- Chert - a fine-grained volcanic stone which comes in several colours. Flakes of this stone made cutting and scraping tools.
- Petrified wood – used to make various tools.
Archaeologists have also found artefacts made from stone that likely came from Nelson. This shows the Polynesian settlers of Aotearoa were geologists, exploring the new land and identifying good quality stone to make tools.
A shell-midden revealed
In 2009 a storm removed sand from White’s Beach in the centre of the island. This exposed a shell midden and a charcoal-rich black layer about 1.5 metres down from the top of the dune. Archaeologists collected samples of shell and charcoal. Sea mammal bones, fish and dog bones were present in the sample. The shell was radiocarbon dated to around the late 1400s.
Moa bones are found in some digs but with all the rich seafood, moa would not have been in the islanders’ daily diet. These birds were probably ferried in by waka. Moa died out within 200 years after human arrival due to predation, so the presence of moa indicates the site is old.
The evidence for gardening
There are 21 former gardening areas in the northern part of Ahuahu. The largest is at Tamewhera in the northwest and is several hectares.
Archaeologists found surface stones arranged into lines down the slope. The lines are single stones placed end on end. In other sites, stones have been piled up to form a row that sticks up above the ground. These are cross walls. Adding soil on the uphill side behind these walls creates deeper soils for better gardens.
Other less obvious garden areas show parallel drains running down a slope. These are now only visible at certain times of the day or season. Kūmara storage pits were often left open when finished with. These are now visible as roughly rectangular depressions in the ground. Kūmara pits are present in several sites, including pā.
Pits on Stingray Point Pā
Two big kūmara pits excavated on Stingray Point Pā (Matakawau) in 1955 must have held a lot of kūmara because there were more than 80 postholes in each pit. Most of them showed rebuilding of the roof structures and later activities on the flat living terrace dug into the infilled pits. There was a complex system of drains inside each pit to remove any water which seeped in through the thatch and soil covering. There were also larger features to drain the water outside the pits.
A reconstruction drawing of how such storage structures may have looked.
Source: https://tmrowe.com/2017/04/03/ahuahu-archaeology-on-great-mercury-island/
Discovery of taro in Māori gardens
New research from the archaeological project shows that taro was an important crop for early Māori on Ahuahu. Leafy greens like pūhā and watercress were important too. Archaeologists have analysed buried sediments from swamps and found the pollen of taro and other leafy greens.
The deposits have been radiocarbon-dated to the 14th century, around 600 to 700 years ago. The gardens on Ahuahu are some of the earliest in New Zealand.
The new evidence suggests that Polynesian gardeners adapted the environment to continue growing their staple food, taro. When they first came here, Māori may have focused on taro and created wetland gardens to grow it. Kūmara then became the main crop after AD 1500.
Taro was an important food in tropical Polynesia. Although the taro didn’t grow very large in the cooler New Zealand climate, the gardeners persisted with trying to grow it because of its links with the homeland, and because it was a chiefly food used in hui. Researchers also thought that pre-European Māori gardens were mostly weed free. But the fossil pollen remains from Ahuahu suggest indigenous edible leafy herbs such as watercress and pūhā were common.
- Archaeology is Amazing - Professor Simon Holdaway leads a team that’s excavating the remains of human settlement on Great Mercury Island.
- Daily video diary - an archaeology student's vlog from an excavation on Ahuahu Great Mercury Island.
