Mātuku Link Wetland Delineation

Background

The Mātūkū Link is a wetland and restoration project located in Te Henga/Bethels beach Te Henga/Bethells Beach, owned and operated by the Mātūkū Reserve Trust. The Mātūkū Link includes over 37 hectares of wetland and forest habitat in the upper reaches of the Te Henga Wetland complex. The complex comprises one of the largest freshwater wetland areas in the Auckland Region, covering approximately 180 ha, and home to range of threatened habitat types and threatened fauna including mātūkū-hūrepo/Australasian bittern, pāteke/brown teal, and mātātā/North Island fernbird.

PDP was engaged to undertake a Significant Ecological Area (SEA) wetland assessment and delineation in the Mātūkū Link. Under the Auckland Unitary Plan, landowners in rural zones can earn Transferable Subdivision Titles for the protection or restoration of significant areas of indigenous vegetation or wetlands. Titles can then either be used or sold to other landowners looking to subdivide within the countryside living zone. This mechanism provides a financial incentive that rewards landowners for protecting, enhancing, and creating good quality indigenous habitat.

The Project

This project assessed the extent of wetland habitat present by undertaking assessments of vegetation, soils, and hydrological conditions. These areas were then assessed against the five criteria for inclusion as a Significant Ecological Area, and whether they can be used to claim Transferable Subdivision Titles. The SEA criteria consider the overall ecological value of indigenous vegetation and wetland habitats including:

Representativeness – Whether the area supports the expected indigenous plant communities for the area.
Threat Status and Rarity – Whether the area supports rare or threatened flora, fauna, plant communities, habitats, ecosystem types or genetic diversity.
Diversity – The overall diversity of indigenous species.
Stepping Stones Migration Pathways and Buffers – Whether the area provides important linkages to nearby habitats.
Uniqueness and distinctiveness - Whether the area has any unique or distinctive features not found elsewhere, such as habitat for species only found in the Auckland Region.

Digital methods of data collection were used to record vegetation, soils, and hydrology to determine the location and extent of wetlands present on the site and allow for precise mapping of wetland extent. Several hectares of wetland were mapped and found to meet the SEA criteria due to the presence of threatened fauna, representative indigenous vegetation, and important habitat linkages to the wider Te Henga Wetland. PDP’s work allowed the Mātūkū Reserve Trust to earn Transferable Subdivision Titles to help fund their ongoing restoration efforts.