‘The paua that clings to the sea’: a new species of abalone found only in waters off a remote NZ island chain

National Museum - Tepapa

It has long been suspected that a small paua (known as abalone, ormers or ear-shells overseas) found around a remote island chain north of Aotearoa New Zealand differs from all other paua.

Our earlier genetic research, using pioneering methods to extract ancient DNA from shells, provided the extra evidence needed.

We could now formally name and describe the new species of paua from the Three Kings Islands/Manawatawhi.

The scientific name of the Manawatawhi paua, Haliotis pirimoana, was proposed by Ngati Kuri, who hold historic and territorial rights over the islands (mana i te whenua). Its name means “the paua that clings to the sea”.

A national treasure

Paua live on shallow reefs around the world, where they graze on algae. Globally, there are about 70 paua species, ranging from “button” to “beret” in size.

Globally, few wild-caught abalone fisheries remain due to overfishing and a “withering disease” that has, fortunately, not been detected in Aotearoa New Zealand.

In New Zealand, we now recognise four living paua species. Three of these – the black-foot paua (Haliotis iris, which grows to about 200mm in size), the yellow-foot paua (H. australis, 120mm) and the virgin paua (H. virginea, 70mm) – are distributed broadly along the coast of mainland New Zealand.

Paua are a taonga (national treasure). Their opalescent shells are iconic: they form the eyes of carvings, were used in traditional fishing lures, and feature in contemporary art and jewellery.

Surprisingly, these wonderful colours are not caused by different pigments. Instead, they result from a layer of shell made of a special form of calcium carbonate that splits light into its component parts, like oil on water.

Recreational harvest of paua as kaimoana (seafood) is a national pastime (as is debate over the best ways to tenderise and cook them). Black-foot paua are also the focus of growing aquaculture and pearl industries.

Why this matters

It’s not every day we discover a new species, although it happens more often than you might think.

Species discovery is seldom punctuated by a clear “Eureka!” moment. More often, it’s a muted thought that something looks a little different. So it was with the discovery of the Manawatawhi paua.

The Manawatawhi paua grows to just shy of 40mm. It is unlikely to have any commercial value or require conservation efforts. However, this species is another in the list of taonga (treasures) unique to Manawatawhi specifically, and to Aotearoa more broadly.

The Manawatawhi island chain lies roughly 60km northwest of Cape Reinga/Te Rerenga Wairua, the northern tip of the North Island. The islands are rugged, remote and beautiful.

Surrounded by deep water, and directly in the path of the Tasman Front which brings warm water from Australia but results in the localised upwelling of cold water, Manawatawhi teems with life. Many of the islands’ coastal and terrestrial species occur nowhere else on Earth.

Manawatawhi is not “pristine”, but the region remains a benchmark showing what much of Aotearoa used to be like. Ngati Kuri are keenly aware of the importance of the taonga in their rohe (tribal area), and they are active in restoration, research and conservation efforts.

Biodiversity research, expertise and reference collections are critical for understanding the structure of regional ecosystems and predicting how they might respond to human activities and the changing climate. Such research provides the evidence necessary for effective fisheries, biosecurity and conservation management. It can ultimately contribute significantly to the economy.

We are in a global biodiversity crisis. Species are going extinct faster than we can discover and name them. The Museum of New Zealand Te Papa Tongarewa and the National Institute of Water and Atmospheric Research (NIWA) recently partnered with Ocean Census to discover hundreds of new species from deep water off southern Aotearoa.

There are, however, thousands of species we have already discovered, which are still awaiting formal names. There are very few biodiversity scientists left in Aotearoa to do this work.

This research reflects our obligation towards future generations so they, too, can enjoy the wonderful richness of our biodiversity.

Nic Rawlence receives funding from the Royal Society Te Aparangi Marsden Fund.

Hamish G Spencer and Kerry Walton do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.