This repository hosts the quantitative ecosystem model of Cockburn Sound, Western Australia, developed using the Ecopath with Ecosim (EwE) framework. The model represents the trophic structure and interactions among key biological components of the Sound — from phytoplankton and invertebrates to fish, birds, and marine mammals.
Ecosystem models aim to represent ecological systems by quantifying interactions among their components, from individual populations to communities and entire biomes.
Among various ecosystem modelling tools, Ecopath with Ecosim (EwE) — an energy-balance trophic model — is one of the most widely applied frameworks globally, with over 800 published models (www.ecopath.org).
The EwE model has been applied in diverse contexts including:
- Ecosystem-based management (Plaganyi & Butterworth)
- Climate change impacts (Brown et al., 2010)
- Fishing and harvest effects (Lozano-Montes et al., 2013)
- Spatial closures (Lozano-Montes et al., 2012)
- Artificial reefs (Wu et al., 2016)
- Aquaculture impacts (Han et al., 2017)
Since its inception in the 1980s (Polovina, 1984), EwE has become the standard for marine ecosystem trophic modelling.
The Cockburn Sound EwE model aims to:
- Characterise the trophic structure, key ecosystem attributes, and overall functioning of Cockburn Sound.
- Integrate historical and recent datasets — from fisheries, ecological monitoring, and the WAMSI Westport research program — into a unified quantitative ecosystem framework.
- Support ecosystem-based synthesis and management strategies for the Sound.
- Quantify food-web interactions to identify key energy pathways and trophic dependencies.
- Explore management and climate scenarios to assess ecological flow-on effects of anthropogenic and environmental changes.
The model development combines:
- Historical fishery datasets
- Data from the WAMSI Westport Program
- Expert input from DPIRD, ECU, Murdoch University, UWA, and CSIRO
The Ecopath software (www.ecopath.org) was used to integrate and quantify these datasets into a cohesive trophic model.
The Ecopath model assesses:
- Intra- and inter-specific competition among functional groups
- Predation dynamics for commercial, recreational, and conservation species
- Energy flow among trophic levels
- Ecosystem impacts of fishing, port development, and climate change
Key ecological groups include target fish species, higher predators (e.g. Australian Sea Lion, Bottlenose Dolphin, Little Penguin, migratory seabirds), demersal and pelagic assemblages, invertebrates, and primary producers.
The EwE framework provides the quantitative basis needed to evaluate potential ecosystem responses under different management and environmental scenarios.
The model domain covers approximately 130.3 km², representing the embayment of Cockburn Sound in the depth range of 0–20 m.
It includes key components of the Sound’s food web:
- Commercially important species
- Recreationally targeted species
- Species of conservation concern
- Demersal and pelagic fish assemblages
- Invertebrates and primary producers
Figure 1: Model domain for the Ecopath Cockburn Sound model, covering approximately 260 km².
A total of 65 functional groups were defined, representing over 80 species based on local biological surveys and expert consultation (DPIRD, ECU, MU, UWA, CSIRO).
Groups were defined to reflect:
- Commercial/recreational significance:
Pink Snapper, Blue Swimmer Crab, Southern Garfish, Sandy Sprat, etc. - Conservation importance:
Little Penguin, Bottlenose Dolphin, Australian Sea Lion, Cormorants, migratory Waders, Sharks
🔗 View the full list of functional groups →
- Polovina, J. J. (1984). Model of a coral reef ecosystem. Marine Ecology Progress Series.
- Plaganyi, E. E., & Butterworth, D. S. (Various years). Ecosystem-based fisheries management applications.
- Brown, C. J., et al. (2010). Impacts of climate change on marine ecosystems.
- Lozano-Montes, H., et al. (2012, 2013). Trophic modelling of Western Australian marine systems.
- Wu, et al. (2016). Ecosystem effects of artificial reefs.
- Han, et al. (2017). Aquaculture impacts in trophic networks.
If you use this model or documentation, please refer to the associated report and citation:
WAMSI-Westport Marine Science Program
📦 CockburnSound-Ecopath-Model
├── model/ # Ecopath model files (.ewemdb)
├── Documents/ # Supplementary documentation and tables
├── Groups/ # Full list of functional groups (tables)
├── Inputs/ # Input data: biomass, diet matrix, catches, etc.
├── Outputs/ # Domain map, trophic diagrams, results
├── README.md # This file
└── LICENSE