• Active project

Scale and EBM

Improving understanding and communication of scale-dependencies for EBM

Project Leader Duration Budget
Joanne Ellis (University of Waikato) April 2022 – December 2023 $400,000


Ecosystem-based management (EBM) is a dynamic process, focused on understanding and managing ecosystems across a range of organisational (eg iwi, hapū and whānau; local councils, regional councils and central government agencies), spatial (eg local, regional, national) and temporal scales (eg past, present and future effects).

Despite the importance of scale, scale-dependency in different disciplines, and the interactions between them, is rarely explicitly stated and acknowledged as affecting both the decision-making process and its success.

While some Sustainable Seas research explicitly focuses on producing results for different scales, there are gaps in understanding of how EBM can be achieved across a variety of scales. Scale also influences components that may have to change if jurisdictional boundaries or management resolutions are changed, such as the prediction of impacts from cumulative interactions, the return periods of events for management, or the creation of spatial and temporal rules for consenting.

To support development of decision-making practices that explicitly identify scale and scale-dependencies to increase the success of EBM decision-making processes we are:

  1. Reviewing existing knowledge of scale dependencies from other Sustainable Seas projects.
  2. Analysing scale-dependencies, specifically in the legal-policy, ecological, socio-psychological, mātauranga Māori and economic realms.
  3. Creating visual summaries to aid understanding of cross-scale implications and contribute to robust, transparent decision making.

Research Team

Joanne Ellis (University of Waikato)
Judi Hewitt (University of Auckland)
Simon Thrush (University of Auckland)
Karen Fisher (University of Auckland)
Taciano Milfont (University of Waikato)
Elizabeth MacPherson (University of Canterbury)
Erica Williams (NIWA)
Eric Jorgensen (Ocean Bay Farm)
Ani Kainamu (NIWA)

Co-Development Partners

Aquaculture NZ
Waikato Regional Council
Bay of Plenty Regional Council
Shane Geange (Department of Conservation)


This is a national project.


  • September 2022
    List of scale-dependencies of tools, models and guidelines from other challenge projects.
  • September 2023
    Policy briefing on categorising risks associated with unintended management failures driven by scales mismatches
  • September 2023
    Analysis of legal approaches to managing issues of scale in marine contexts
  • December 2023
    Methodologies to assess and display scale mismatches developed and used to communicate scale-dependencies
  • December 2023
    Visual summaries demonstrating cross scale implications or barriers related to cumulative effects and recovery actions