Whangapoua

Size: 615 hectares

Site description

The Whangapoua biodiversity focus area is on the north-east coast of Aotea / Great Barrier Island. The biodiversity focus area encompasses Whangapoua estuary and beach, as well as native vegetation and streams which extend from the estuary up towards Okiwi.

Whangapoua beach and estuary.
Looking east over the Whangapoua beach and into the estuary.
Photo credit: Andrew Macdonald, Biospatial Ltd 2019

Key ecosystems

This biodiversity focus area contains one of Tāmaki Makaurau / Auckland’s largest estuarine ecosystems with mangroves, saltmarsh, salt-meadow and shallow tidal flats (SA1). This is protected on the eastern side by a long sandspit and sandy beach with extensive sand dunes (DN2 and DN5).

Inland, the estuary transitions into large freshwater wetland mosaics (WL10, WL11, WL12, WL18, WL19). The healthy vegetation, with its rich species diversity and intact sequences from one ecosystem to another, is of extremely high biodiversity value.

Whangapoua coastal wetland and dune.
Looking west over Whangapoua coastal wetland and dune complex.
Photo credit: Andrew Macdonald, Biospatial Ltd 2019

Native fauna

The varied and extensive areas of habitat and abundance of food sources support a diverse range of native species. Wetland birds present include:

  • mātātā (fernbird)
  • mioweka (banded rail)
  • pūweto (spotless crake)
  • matuku hūrepo (Australasian bittern).

A diverse range of shorebird species utilise this area including:

  • tūturiwhatu (New Zealand dotterel)
  • tōrea pango (variable oystercatcher)
  • pohowera (banded dotterel)
  • kuaka (bar-tailed godwit).

Whangapoua estuary is the main strong-hold for pateke (brown teal) on Aotea / Great Barrier Island. There are also native lizard populations within this area.

The sequence and connections between streams, freshwater wetlands and the estuary provide an excellent freshwater habitat. Native fish found here include:

  • giant kōkopu
  • banded kōkopu
  • inanga
  • koaro.

Threats

Pest plants, rabbits and other animal pests threaten the integrity of the estuarine, wetland and dune vegetation and overall ecosystem health.

Related ecosystems

Active coastal sand dunes ecosystem

Spinifex, pīngao grassland or sedgeland ecosystem (DN2)

Dunelands occur where erosion and accretion of sand creates mobile dune systems. Due to the extreme conditions only a few highly specialised, drought tolerant plant species have adapted.

Threat status
Endangered

Active coastal sand dunes ecosystem

Oioi, knobby clubrush sedgeland ecosystem (DN5)

Large dune plains such as those at Whatipū and Papakanui Spit occur with accreting coastlines behind mobile dunes. The mosaic of dry and ephemeral plant communities provide habitat for many native fauna.

Threat status
Critically endangered

Coastal saline ecosystem

Mangrove forest and scrub ecosystem (SA1)

Mangrove forest and scrub is found in tidal estuaries, inlets and where salt water meets fresh at the mouths of rivers and streams. This ecosystem has a range of distinct plant communities that provide habitat for birds and fish.

Threat status
Least concern

Coastal saline ecosystem

Herbfield (coastal turf) ecosystem (SA5)

This ecosystem occurs on hard rock on coastal bluffs and cliffs along the western coastline of Auckland and some Hauraki Gulf islands. A wide range of salt-tolerant herbs, sedges and rushes are present.

Threat status
Critically endangered

Wetland ecosystem

Oioi, restiad rushland and reedland ecosystem (WL10)

Typically found on coastal stream margins where freshwater meets saline, this ecosystem is characterised by abundant oioi. Mātātā (fernbird), matuku (Australasian bittern), banded rail (mioweka) may be present in some areas.

Threat status
Endangered