Omanawanui Coastal Forest

Size: 56 hectares

Site description

The Omanawanui Coastal Forest biodiversity focus area extends along the coast from the southern end of Whatipu to Little Huia in the Waitākere Ranges. Paratutae Rock, situated on the northern side of the entrance to Manukau Harbour, is also included.

Omanawanui ridge on the Manukau Harbour.
Coastal forest along the Omanawanui ridge which runs along the Manukau Harbour towards Whatipū. Significant stands of young kauri ricker are also present along the edge of the Manukau Harbour.
Photo credit: Andrew Macdonald, Biospatial Ltd 2019

Key ecosystems and vegetation

This biodiversity focus area includes a mix of coastal forest (WF4) and pōhutukawa treeland/flaxland/rockland (CL1) on cliffs and hillslopes which rise steeply from the Manukau Harbour. The land here is rugged and volcanic.

The dominant canopy trees in the coastal forest are:

  • pōhutukawa
  • karaka
  • nīkau
  • pūriri
  • kōwhai
  • tawāpou
  • houpara
  • mamangi
  • rewarewa.

Vegetation on the cliffs and on Paratutae Rock includes a mix of pōhutukawa, flax, houpara, coastal astelia and salt-tolerant native herbs. 

Paratutae Island.
Paratutae Island and coastal forest at Whatipū.
Photo credit: Andrew Macdonald, Biospatial Ltd 2019

Habitat value

The coastal forest provides valuable habitat and food sources for common native forest birds including:

  • kererū
  • tūī
  • kōtare (kingfisher)
  • pīwakawaka (fantail)
  • riroriro (grey warbler)
  • tauhou (silvereye).

The large native trees overhanging the shoreline also provide roosting and nesting habitat for shag species.

Omanawanui ridge and the Manukau Harbour.
Looking east over the Omanawanui ridge, into the Manukau Harbour.
Photo credit: Andrew Macdonald, Biospatial Ltd 2019

Management

Coastal weeds controlled by Auckland Council in this area include Mexican daisy, agapanthus, pampas, wild ginger and Formosan lily.

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

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