Supplementary Report to the Final Report of the Coral Reef Expert Group: S7. Coral reef models as assessment and reporting tools for the Reef 2050 Integrated Monitoring and Reporting Program – a review
The objective of this report is to review the existing models of temporal/spatial dynamics of coral communities available for the Great Barrier Reef (the Reef), with the specific aim at evaluating their strengths and weaknesses for the assessment and reporting of coral reef health within the Reef 2050 Integrated Monitoring and Reporting Program (RIMReP). Focusing on peer-reviewed articles available by 28 February 2018, we found that a variety of modeling approaches exists yet with different scope, level of complexity, and ability to represent the various processes driving the dynamics of coral populations. Tools available to model Reef coral population dynamics also vary in their capacity to capture the spatial heterogeneity of coral populations and their environment, the variability of disturbance impacts and the uncertainty around current reef state and possible future trajectory. The various characteristics and properties exhibited by coral reef models means they have different capacities to complement reef monitoring and assessment on the Reef. This review provides guidance for integrating a modeling component to RIMReP by identifying the modeling approaches that offer the strongest support to reef monitoring and management.
The report is organised as follows: In section 1, we list the potential benefits of ecological models for monitoring programs and explain how models can complement monitoring data and support the assessment of reef status and trends across the Reef. Section 2 provides an overview of the general characteristics and properties of ecological models, with the aim of facilitating the technical comparison of available coral reef models. In section 3, we summarise what we think are the key processes that influence the dynamics of coral populations. This provides a mechanistic framework allowing a comparison of models based on their ecological realism, i.e. their ability to reproduce changes in coral populations from the compounded action of individual demographic mechanisms. Section 4 provides an overview of the candidate coral models for the Reef, with their summary characteristics (model type, state variables, time steps), the ecological processes embedded, their parametrisation and model’s ability to capture the spatial dynamics of corals in a heterogeneous environment. For each model we highlight their strengths and weaknesses in complementing monitoring data to inform about status and trends across the Reef. Finally, we synthesise in section 5 the best candidate models, highlight their ability to inform management priorities for the Reef and make a number of recommendations for a successful integration into RIMReP.