Okura Bush and Shell Barriers

Size: 164 hectares

Area description

The Okura Bush and Shell Barriers biodiversity focus area is located at the southern end of the Rodney Ecological District. It includes Okura Estuary Scenic Reserve, administered by the Department of Conservation, on the northern side of the Okura River, and an esplanade reserve along the coastal margin of Karepiro Bay.

The native forest is large and almost continuous with a mix of mature and regenerating forest and scrub ecosystems. There are freshwater streams with good connections to the marine environment. This biodiversity focus area has an important, intact vegetation sequence from forest to estuary.

Okura Scenic Reserve.
The shellbarrier beach and surrounding mangroves of Okura Scenic Reserve in Rodney.
Photo credit: Andrew Macdonald, Biospatial Ltd 2018

Key ecosystems

Mature and diverse coastal forest (WF4) and pōhutukawa treeland (CL1) form a band along the coastal edge. Further inland on steep hillslopes, there are large patches of kauri, podocarp, broadleaved forest (WF11) of varying ages. The kauri forest includes native plants commonly found growing in association with kauri trees such as the kauri greenhood orchid. 

Regenerating forest and scrub dominated by kānuka (VS2), links what is left of the older forest remnants. The scrub contains many native species often associated with gumland vegetation.

At sea level, the forest grades into estuarine vegetation which is protected as part of the Long Bay-Okura Marine Reserve. There are mangroves, intertidal flats, saltmarsh and a shell barrier beach. Shell barrier beaches are considered to be a naturally uncommon ecosystem type. Further around the coast to the north is Karepiro Beach.

Okura river at low tide.
Dacre point and the entrance to the Okura river during low tide.
Photo credit: Andrew Macdonald, Biospatial Ltd 2018

Key species

The shell barrier beach and Karepiro Beach provide important habitat for migratory and resident shorebirds including:

  • tōrea (South Island pied oystercatchers)
  • kuaka (bar-tailed godwits).

Both species have a threat status nationally of At Risk – Declining.

Surveys of the forest show a diverse range of native plant species, including several nationally and/or regionally threatened plants. The forest, streams, and estuarine and beach habitat supports a number of freshwater fish, lizard and bird species. 

The Okura Bush and Shell Barriers biodiversity focus area lies within the North-West Wildlink area. It provides an important stepping stone for birds moving across the landscape.

Okura Scenic reserve, Long Bay.
Looking down on Okura Reserve catchment towards Long Bay. Significant stands of kauri populate the area.
Photo credit: Andrew Macdonald, Biospatial Ltd 2018

Kauri dieback

Some of the kauri trees within the reserve are infected with kauri dieback, a soil-borne pathogen capable of killing kauri trees of all ages. Public access is currently restricted to prevent further spread of kauri dieback.

Okura Scenic Reserve.
Tall stands of kauri ricker amongst other podocarp, broadleaved species with coastal forest along its edges.
Photo credit: Andrew Macdonald, Biospatial Ltd 2018

Related ecosystems

Cliff ecosystem

Pōhutukawa treeland, flaxland and rockland ecosystem (CL1)

This ecosystem occurs on coastal rock faces and eroding hill-slopes around the Auckland coastline and on offshore islands. It contains a mosaic of different plant communities including herbs, flax, shrubs and trees.

Threat status
Vulnerable

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

Regenerating ecosystem

Kānuka scrub and forest ecosystem (VS2)

Found throughout New Zealand, kānuka dominated forest establishes readily after fire. It's diverse range of flowering and fruiting shrubs and trees provide habitat for a wide range of invertebrates, birds and lizards.

Threat status
Least concern

Warm forest ecosystem

Kauri, podocarp, broadleaved forest ecosystem (WF11)

Once widespread across the Auckland region, this warm forest ecosystem contains a range of podocarp and broadleaf trees on different landforms. It is an ideal habitat for birds, bats and lizards thanks to an abundance of fruit and nectar.

Threat status
Endangered

Warm forest ecosystem

Pōhutukawa, pūriri, broadleaved forest ecosystem (WF4)

Scattered along Auckland's coastlines, this broadleaved forest ecosystem provides an important source of food for kererū. They are also important seed dispersers for many species in this ecosystem.

Threat status
Endangered