An Investment in Our Future

Overview

Currently in New Zealand, there are several important wetlands’ management and restoration activities being carried out by local councils, iwi, community groups, Fish & Game and the Department of Conservation. Most importantly, an increasing number of landowners are now seeing the value and importance in restoring these unique landscape features. 

In 2020, the New Zealand Government introduced the National Policy Statement on Freshwater Management (NPS-FM) regulatory package with the aim of embedding long-term change through regional plans, including policies to protect and restore wetlands. These policies mandate that each council - including the Otago Regional Council - must map all New Zealand’s natural inland wetlands of a minimum 0.05 hectares and lesser if contain threatened species or ephemeral, by 2030.

A unique example of nationally and internationally significant wetlands are right here in Otago, and contained within the Upper Taieri Scroll Plain, a series of wetlands in the upper reaches of the Taieri River, the only wetlands of its kind in New Zealand.

The Upper Taieri Wetland Complex consists of three sub-areas, the Styx (Paerau) Basin Wetlands, the Maniototo Basin Wetlands and Taieri Lake Wetlands. These areas are predominantly in private ownership and much of this area comprises pastureland used for grazing. However, most of these pasture areas retain significant wetland values, including being home to many threatened and critically endangered species of plants, fish, and birds.

Mapping the Upper Taieri wetlands

Under the Government’s directive, in 2021-2022, the Otago Regional Council commenced Phase One of a three phase project, mapping and delineation of the wetlands in the Upper Taieri Scroll Plain wetland complex. Working alongside the landowners and community groups, this task is expected to be completed by the end of 2022.

The mapping involves reporting on wetland hydrology, river water level, ground wetness, land curvature and the likelihood of land to be wet in an event of annual and seasonal high-water levels. Alongside wetlands hydrology and the scroll plains topography, the wetlands’ current state will also be assessed on its plant diversity (regardless of whether indigenous or non-indigenous species) and the proportion of the area that is dominated by plants that prefer wet soils/conditions. Vegetation cover will be ranked on the basis of the plants’ preference for wet, dry or intermittent conditions. If more than 50% of the vegetation cover consists of species that prefer or tolerate wet conditions, then the area is considered to be a wetland.

Phase Two consists of mapping and delineating regionally significant wetlands, which will also be completed in 2022. Phase Three, involving the mapping of all natural wetlands in the region, will be completed by 2030 prioritising those at risk followed by those identified in areas under development.

During these phases we will be actively engaging with local communities. If you are an owner of the areas being mapped, and you would like to know more, please check out our FAQs, or contact Dr Sami Khan (Sami.Khan@orc.govt.nz). You can also keep up to date on general water related work the ORC is doing by subscribing to On-Stream.

What are wetlands delineation and the protocols involved?

The NPS-FM 2020 guidelines suggest that in case of uncertainty or dispute about the existence or extent of a natural wetland (as identified in the maps), a regional council must have regard to the Wetland Delineation Protocols (WDPs).

New Zealand’s Ministry for Environment (MfE) has adopted a US based wetland delineation system, which uses three main criteria, i.e., vegetation, soils, and hydrology. These criteria have been adapted for New Zealand conditions and the "Wetland delineation protocols" are available on the MfE website

Why are we focusing on the Upper Taieri wetlands?

New Zealand’s wetlands are one of the world's most productive environments that support the greatest concentration of wildlife out of any other habitat.

They act like the kidneys of the earth, cleaning the water that flows into them. They trap sediment and soils, filter out nutrients and remove contaminants; can reduce flooding and protect coastal land from storm surge; are important for maintaining water tables; they also return nitrogen to the atmosphere. Wetlands also sequester carbon from the atmosphere through plant photosynthesis and by acting as sediment traps for runoff. Carbon is held in wetlands vegetation as well as in litter, peats, organic soils, and sediments that have built up, in some instances, over thousands of years.

The Taieri Scroll Plain Wetlands are situated around the Taieri River, which is the fourth longest river in New Zealand and follows an s-shaped course from the Central Otago block mountains to the sea near Dunedin. The upper catchment is a mosaic of tussock grasslands, farmland, wetlands and bogs which help store water and release it slowly into the river, protecting fish, wildlife and cultural values, and water sources.

The river is habitat for several of New Zealand's 27 native fish species including inanga, short-finned eels, kokopu and bullies. Four threatened species are found in this area: the Central Otago roundhead galaxias, dusky galaxias, Teviot flathead galaxias and the Taieri Flathead galaxias. 

The Taieri scroll plain wetlands are also one of the top waterfowl sites in New Zealand. Among the 28 bird species recorded, the wetlands are home to the endangered black-billed gull, grey duck, white heron, black-fronted tern, and the nationally threatened Australasian Bittern and the Banded Dotterel.

Migrating birds visiting Otago’s wetlands are also an important reminder of our global connections and responsibilities, with some birds travelling thousands of kilometres non-stop to reach our wetlands.

Upper Taieri Mapping Q&As