Ecosystem health

The Ecosystem Response theme aims to characterise and understand the ecological responses to contaminant stressors, for example algal growth from resulting from elevated nutrient discharge. The main stressors to be considered are elevated sediment, faecal and nutrients concentrations and loads to each type of receiving environments.

By characterising the system a better understanding of how the system functions and which stressors are likely to dominate the system can be achieved, which will lead to better decision-making for those ecosystems.

The Ecosystem Response theme has been divided into sub-themes that correspond with the different receiving environments:

  • Southland’s estuaries - This theme will identify loads to meet a gradient of environmental conditions, and provide a timeline relating estuary condition and loads at specific time periods.
  • Human health - Determining the origin of microbial contamination of surface waters, drinking waters and shellfish.
  • Freshwater ecosystem health - The proposed monitoring system, an expansion of an existing network, aims to facilitate the separation and characterisation of anthropogenic and natural stressors and pressures, on waterway health and provide an assessment of regional progress toward objectives and targets.
  • Mountain and lowland lakes - Characterisation and GIS-based risk assessment of lakes and followed by catchment modelling to link land management to the lake’s ecosystem response.


A review of benthic macroinvertebrate metrics for assessing stream ecosystem healthThis report examines the suitability of additional/new macroinvertebrate metrics to report on fresh water ecosystem health.
A review of the ecological health, water quality and drivers of change in four Southland estuaries - NIWAThis report outlines the results of an assessment of the ecological health of four Southland estuaries (Jacobs River Estuary, New River Estuary, Waikawa and Toetoes) using existing monitoring data.
Drivers of Estuary Ecological Health and Water Quality in the southland RegionThis report is a companion report to the above and outlines the main drivers of estuary ecological health and water quality in the region (nutrients and fine sediments).
Ecological health assessment for Southland lakesThis report outlines the results of a study to select and develop a framework for assessing ecological conditions in lakes and the subsequent application of this framework to Southland’s lakes.
Longfin Tuna and Brown Trout Habitat Quality Indices for Interpreting Habitat Quality Score DataThis report outlines Habitat Quality Indices for Longfin Tuna and Brown Trout. It builds on current rapid habit assessment and provides scores which are species specific.
Scientific approach for Southland EstuariesThis report provides an overview of the Southland Estuary Health Programme and collates the various reviews of this programme and responses to the recommendations in the reviews.
Sheep as a potential source of microbial contamination in SouthlandThis report highlights that the impact of ovine faeces on water quality in Southland and New Zealand needs to be recognised and addressed.
Wetland Inventory Project 2015-16 PART 1This brief report outlines progress since the 2015 Wetland Inventory report, and summarises additional results. Approximately 99% of lowland, 13% of hill country, and 41% of inland basin categories have been compared between 2007 and 2015.
Wetland Mapping Project report 2014-15This report provides an outline of project inventorying wetlands on non-public conservation land in Southland. The report identifies the total wetland area lost in Southland between 2007 and 2014.