On the main beach of Ōtata Island is a large, historic midden, made up of layers of shells, animal bones and other archaeological evidence. A midden can be read, much like an encyclopedia, to teach us about events geological, weather or fires, and also the presence of animals and humans. That ‘encyclopedia’ of biological material sits alongside the oral histories of mana whenua, as well as the information gathered over the years by the Neureuter family. Sadly, up to five metres of that midden were lost in a large storm in January 2018.

Aware of the need to preserve the midden before it degraded further, Auckland Museum Archaeologists Dr Louise Furey and Emma Ash worked in collaboration with mana whenua, Ngāi Tai ki Tāmaki, and the Neureuter family, to undertake excavations of the Ōtata midden, with digs taking place during the March 2020 and again in February 2021.

In the first dig, the team excavated three 1x1m sq sections by the bucketload, with the contents of each bucket sieved, bagged, numbered and details noted. At the end of the excavation, soil and rocks were returned to the hole they came from and bags were filled with shell, bone and charcoal. The 400 bags weighed between 1 and 3kgs each.

Back at the Museum, samples were sorted and placed in large bins according to square and layer, then put in the Museum’s walk-in freezer for two weeks to kill any insects or bugs before being sent to the lab.

Sorting is always laborious, with each bag weighed then tipped into a tray while identifiable shells are sorted into piles, and charcoal and bone fragments placed in their respective piles as fragments are worked through. Once all the shell fragments have been sorted and whole shells counted, this gives an indication of the number and proportion of each species in the bag, providing quantitative data on what people were eating, reflecting both availability and personal preference.

“We will learn what Māori were doing on the island at different times by analysing each layer,” Louise explains. “There is tephra (ash) from Rangitoto separating the two lower cultural layers indicating that the island was first occupied before Rangitoto existed. Storms are also recorded within the profile of the bank – small pebble layers and a thick layer of beach shell to show the island had been subjected to serious storm events in the past.”

The thing that most surprised Louise was finding Rangitoto tephra. “There are very few known sites in Auckland from the 14th century, because of erosion and coastal development. So, this is a rare site, offering a glimpse of what the Gulf was like at that time. There is even a kaka bone in the lower layer.”

This partnership between Auckland Museum and mana whenua is part of the new bicultural approach for how archaeologists and iwi interact. It’s also an active response to coastal erosion with the common goal of gathering information from vulnerable sites in the Hauraki Gulf.

Read blogs from archaeologist Emma Ash here (2020 and 2021)

Listen to RNZ coverage here.

Inspecting the midden, January 2020. Photo: Katina Conomos.