Phase two is focussed on expanding our ecological knowledge base about estuarine ecosystem health, resilience and functioning, with the development of relevant modelling and indicators to foster effective decision making of estuaries. There are various projects within this Phase, including input from a wide variety of stakeholders and end user groups. Key researchers involved in this phase include ecological and coastal scientists and modellers at Cawthron Institute and the University of Waikato, with input from all other collaborating researchers in OTOT.

Research Aim 3 (RA3) – Estuarine Ecological Understanding, Modelling and Analysis

In our previous MBIE programme (MTM, 2009-2015; MAUX0907) we undertook an intertidal ecological survey of Tauranga Harbour. In the survey, we measured the amount of metals (Zn, Cu, Pb), total nitrogen (TN), total phosphorus (TP), Chlorophyll a, organic content, sediment grain size, in addition to a complete taxonomy of benthic animals, at 75 intertidal sites. As part of OTOT, we are undertaking a sub-tidal survey of Tauranga Harbour, measuring most of the same parameters as in the intertidal survey.

Together with additional data from research by Waikato and Bremen Universities and BOPRC, we will use data from these surveys to model the Harbour’s ecology as affected by anthropogenic and non-anthropogenic forcing factors. A number of statistical methods will be used to disentangle the ecological effects of various pressures on the Harbour’s ecology, for instance by developing statistical models of how particular species respond to different stressors.

We are also developing a hydrodynamic model of the Harbour which, together with land use and runoff models, will enable us to estimate the spatial distribution of sediment, nutrients and other contaminants within the Harbour. Combining this with our species response models, we aim to estimate the effects on different land use scenarios on several species in different parts of the harbor. This knowledge of the Harbour’s ecology will also inform Research Aims 4 and 5.

This RA has the following steps:

  • Sub-Tidal Survey of Tauranga Harbour
  • Hydrodynamic Modelling of the Harbour
  • Predictive Ecological Modelling of the Harbour
  • Improvement of the Ecological Modelling of the Harbour
  • Improved Understanding of Tipping Points in Estuarine Ecology

Research Aim 3 Progress Updates

Research Aim 4 (RA4) – Ecological Indicators for Estuaries

Using data collected by regional councils using the Estuarine Monitoring Protocol (EMP) in estuaries around New Zealand, the research team will assess a number of indicators of estuarine ecosystem health to identify indicators that are useful for environmental managers.

These indicators will be linked to the ecological and spatial planning models developed in this project to generate maps that show the health of Tauranga Harbour at many different locations

This RA has the following steps:

  • Ecological Quality Indicators
  • Estuarine Resilience Indicators
  • Estuarine Early Warning Indicators
  • Incorporate indicators into spatial planning tool

Research Aim 4 Progress Updates

The Oranga Taiao Oranga Tāngata Project builds on the work undertaken in MTM, and will develop toolsets that assist Iwi and Hapū with co-management of Estuaries. By restoring the health of the Estuarine Environment, we also enhance health of the People.