2.1: Benthic habitat distribution in Cockburn Sound and surrounds
Theme: Benthic habitats and communities
Researchers R.K. Hovey, K. Markey, M. Lyons, K. Kilminster (2025)
Identifying options to inform significant seagrass restoration in Cockburn Sound.
Temperate seagrasses are a critical part of the shallow benthic habitats in Cockburn Sound, providing essential ecosystem functions and services. Between the 1960s and 70s, the region experienced a dramatic decline in seagrass coverage, losing approximately 80% of its original extent due to industrial impacts. In recent decades, natural regrowth and targeted restoration efforts have led to gradual recovery, with current coverage estimated at around 25% of pre-industrial levels.
This study mapped the spatial extents of seagrass coverage in Cockburn Sound, Owen Anchorage and Gage Roads, and identified areas with potential seasonal variation, particularly in ephemeral species.
To accurately map seagrass distribution, the study employed two complementary techniques: satellite remote sensing and species distribution modelling. These methods were underpinned by four key components: training data acquisition and curation, image and covariate data generation, machine learning classification and validation.
The results highlight the potential of satellite imagery to map large-scale seagrass habitats and inform management decisions.
How Westport will use the report
Westport will apply the findings of this research to guide and strengthen its environmental management of seagrass in Cockburn Sound throughout the development process. The study has also helped identify priority areas for restoration, which will inform Westport’s strategy to significantly expand seagrass restoration efforts both prior to and following construction activities.
Benthic habitat mapping is a key component of Westport’s environmental impact assessment.
