''Durvillaea poha'' is a large, robust species of southern bull kelp found in

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Discovery

The species was previously classified as the "cape" lineage of ''

Durvillaea antarctica ''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal eros ...

'', but in 2012 it was recognised as a distinct species due to consistent genetic, morphological and ecological differences. In southern New Zealand, ''D. poha'' and ''D. antarctica'' frequently grow next to one another, although ''D. poha'' normally grows higher up or further back on rock platforms, or in more sheltered bays, where wave force is weaker. ''D. poha'' generally has wider fronds than ''D. antarctica'', and can appear more 'orange' across the frond area. Mitochondrial

introgression Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Intr ...

has been observed between the two species, where some plants in Wellington exhibited the nuclear DNA of ''D. poha'' but also mitochondrial DNA belonging to ''D. antarctica''.

Etymology

The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

is from

pōhā Pōhā are traditional Māori bags made from southern bull kelp, which are used to carry and store food and fresh water, to propagate live shellfish, and to make clothing and equipment for sports. Pōhā are especially associated with Ngāi Tah ...

, storage bags made by

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

out of kelp fronds.

Description

The species has wide, air filled blades with a 'honeycomb' structure, and relative stout, pale or orange stipes. The stipes are unbranched.

Distribution

The species is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to New Zealand, and is predominantly found along southern coasts of the South Island and on

Stewart Island Stewart Island ( mi, Rakiura, ' glowing skies', officially Stewart Island / Rakiura) is New Zealand's third-largest island, located south of the South Island, across the Foveaux Strait. It is a roughly triangular island with a total land ar ...

, as well as on the subantarctic Snares and

Auckland Islands The Auckland Islands (Māori: ''Motu Maha'' "Many islands" or ''Maungahuka'' "Snowy mountains") are an archipelago of New Zealand, lying south of the South Island. The main Auckland Island, occupying , is surrounded by smaller Adams Island, ...

. Based on genetic data, the species appears to have undergone a recent range expansion into the North Island, as it can be found at low frequencies along the Wellington coastline. This range expansion coincides with areas affected by tectonic uplift and landslides caused by historic earthquakes, including the 1855 Wairarapa earthquake. The removal of ''D. antarctica'' and formation of new coastline by such tectonic disturbance likely provided an ecological opportunity for ''D. poha'' to successfully colonise coastline north of the Cook Strait.

Human use

Māori culture

Along with '' D. antarctica'', blades of ''D. poha'' are used to make traditional

bags, which are used to carry and store food and fresh water, to propagate live

shellfish Shellfish is a colloquial and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater envir ...

, and to make clothing and equipment for sports. Pōhā bags are especially associated with the

Ngāi Tahu Ngāi Tahu, or Kāi Tahu, is the principal Māori (tribe) of the South Island. Its (tribal area) is the largest in New Zealand, and extends from the White Bluffs / Te Parinui o Whiti (southeast of Blenheim), Mount Mahanga and Kahurangi Poi ...

people, and are often used to carry and store muttonbird (tītī) chicks.

References

External links

Algaebase: ''Durvillaea poha'' C.I.Fraser, H.G.Spencer & J.M.Waters

Museum of New Zealand Te Papa Tongarewa: ''Durvillaea poha'' C.I.Fraser & J.M.Waters (Species)
{{Taxonbar, from=Q21261589 Fucales Flora of New Zealand Edible seaweeds Protists described in 2012