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Coral reefs have been heavily affected by elevated sea-surface temperature (SST) and coral bleaching since the late 1980s; however, until recently coastal reefs of north-western Australia have been relatively unaffected compared to Timor Sea and eastern Australian reefs. We compare SST time series with changes in coral cover spanning a period of up to 36 years to describe temporal and spatial variability in bleaching and associated coral mortality throughout the Pilbara–Ningaloo region. Declines in coral cover ranged from 12.5 to 51.3%, with relative declines ranging from 38 to 92%. Since 2013, coral cover throughout the region has declined to historically low levels at four of five subregions, with impaired recovery occurring at two subregions. Observations are consistent with global trends of repeated severe heat waves, coral bleaching and acute declines in coral cover. Locations within this study region have already experienced multiple coral-bleaching events within a period of less than 5 years. There is a high likelihood that reefs in the western Pilbara and northern Ningaloo regions will experience more frequent marine heatwaves, coral bleaching and mortality events in the future. Action, therefore, needs to be taken now to support the resilience of coral reef ecosystems in the region, which is arguably the most important coral-reef province on Australia’s western coast.

In 2017, the Australian Institute of Marine Science and its partners commenced the North West Shoals to Shore Research Program. The program is designed to address significant scientific and environmental knowledge gaps pertinent to the management of the offshore petroleum industry, a key stakeholder in this ecologically and commercially important region of Australia. The program comprises four themes. 1. Marine noise monitoring and impacts: includes two seismic source (2600 cubic inch air-gun array) exposure experiments have been conducted to investigate selected responses by demersal fishes and pearl oysters across different spatial and temporal scales. 2. Seabed habitats and demersal biodiversity: seeks to understand the physical and biological characteristics of the ancient coastline key ecological feature around the 125 m depth contour and pearl oyster habitats offshore from Eighty Mile Beach. The work examines the ecological processes that maintain benthic communities on both ancient and contemporary coastlines 3. Protected and iconic species movement, distribution and threats: uses innovative sampling techniques to confirm biologically important areas for pygmy blue whales, hawksbill and green turtles. This will assist the quantification and mitigation of the risks vessel movements, industrial infrastructure and activities pose to marine megafauna on the Northwest Shelf. 4. Spatial dynamics of isolated coral reef atolls: develops a habitat model and adaptive monitoring program that informs the future condition of these remote coral reef atolls. Significant progress has been made by the program in 2018, including the development of innovative and technical approaches to sampling.

In 2017, the Australian Institute of Marine Science and its partners commenced the North West Shoals to Shore Research Program. The program is designed to address significant scientific and environmental knowledge gaps pertinent to the management of the offshore petroleum industry, a key stakeholder in this ecologically and commercially important region of Australia. The program comprises four themes. 1. Marine noise monitoring and impacts: includes two seismic source (2600 cubic inch air-gun array) exposure experiments have been conducted to investigate selected responses by demersal fishes and pearl oysters across different spatial and temporal scales. 2. Seabed habitats and demersal biodiversity: seeks to understand the physical and biological characteristics of the ancient coastline key ecological feature around the 125 m depth contour and pearl oyster habitats offshore from Eighty Mile Beach. The work examines the ecological processes that maintain benthic communities on both ancient and contemporary coastlines 3. Protected and iconic species movement, distribution and threats: uses innovative sampling techniques to confirm biologically important areas for pygmy blue whales, hawksbill and green turtles. This will assist the quantification and mitigation of the risks vessel movements, industrial infrastructure and activities pose to marine megafauna on the Northwest Shelf. 4. Spatial dynamics of isolated coral reef atolls: develops a habitat model and adaptive monitoring program that informs the future condition of these remote coral reef atolls. Significant progress has been made by the program in 2018, including the development of innovative and technical approaches to sampling.

Field experiments investigated the effect of acute sedimentation on polyp injury, mortality and bud production in the mushroom coral, Fungia fungites (Linnaeus, 1758). Small (3-5 cm), medium (8-12 cm) and large (15-20 cm) polyps were covered with a layer of sediment in low (2 mm), medium (5 mm) and high (10 mm) treatments, every two days for 20 days. Injury decreased with polyp size, and increased with the amount and duration of sediment addition. Only medium and large polyps briefly (