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This study represents the first ROV-based exploration of the Perth Canyon, a prominent submarine valley system in the southeast Indian Ocean offshore Fremantle (Perth), Western Australia. This multi-disciplinary study characterizes the canyon topography, hydrography, anthropogenic impacts, and provides a general overview of the fauna and habitats encountered during the cruise. ROV surveys and sample collections, with a specific focus on deep-sea corals, were conducted at six sites extending from the head to the mouth of the canyon. Multi-beam maps of the canyon topography show near vertical cliff walls, scarps, and broad terraces. Biostratigraphic analyses of the canyon lithologies indicate Late Paleocene to Late Oligocene depositional ages within upper bathyal depths (200-700 m). The video footage has revealed a quiescent 'fossil canyon' system with sporadic, localized concentrations of mega- and macro-benthos (∼680-1,800 m), which include corals, sponges, molluscs, echinoderms, crustaceans, brachiopods, and worms, as well as plankton and nekton (fish species). Solitary (Desmophyllum dianthus, Caryophyllia sp., Vaughanella sp., and Polymyces sp.) and colonial (Solenosmilia variabilis) scleractinians were sporadically distributed along the walls and under overhangs within the canyon valleys and along its rim. Gorgonian, bamboo, and proteinaceous corals were present, with live Corallium often hosting a diverse community of organisms. Extensive coral graveyards, discovered at two disparate sites between ∼690-720 m and 1,560-1,790 m, comprise colonial (S. variabilis) and solitary (D. dianthus) scleractinians that flourished during the last ice age (∼18 ka to 33 ka BP). ROV sampling (674-1,815 m) spanned intermediate (Antarctic Intermediate Water) and deep waters (Upper Circumpolar Deep Water) with temperatures from ∼2.5 to 6°C. Seawater CTD profiles of these waters show consistent physical and chemical conditions at equivalent depths between dive

Woman found dead off Perth after suspected shark attack.

Woman found dead off Perth after suspected shark attack.

Walkers spot bull shark as it swims near Perth marina - video.

Walkers spot bull shark as it swims near Perth marina - video.

Naval power: Mauritius looks to Perth base for renewable energy solutions.

Two Perth fishermen catch hammerhead shark off Geraldton beach.

SHARK Bay and the coastline off Karratha and Perth may be popular eateries for whale sharks (Rhincodon typus), satellite tracking has revealed.

SHARK Bay and the coastline off Karratha and Perth may be popular eateries for whale sharks (Rhincodon typus), satellite tracking has revealed.

Shark detection technology that can 'x-ray' Perth beaches with drones.

Ben GERRING, a 29-year-old mine worker, was surfing at Falcon Beach south of Perth when he was mauled by a shark and has reportedly lost a leg.

Ben GERRING, a 29-year-old mine worker, was surfing at Falcon Beach south of Perth when he was mauled by a shark and has reportedly lost a leg.

Welcome to Murdoch University, Perth, Western Australia. We're proud to have more than 18,000 students and 1,400 staff from all over the world.

Welcome to Murdoch University, Perth, Western Australia. We're proud to have more than 18,000 students and 1,400 staff from all over the world.

Jean-Luc VAN DEN HEEDE on course to reach Hobart film drop on Friday.

Two drifting wave buoys deployed along the coast of Western Australia by researchers at The University of Western Australia have highlighted the significance of Perth's recent super storm, recording massive waves along 1000km of WA's coastline.

A new study by researchers at The University of Western Australia has found a critically endangered species of hammerhead shark in Perth metropolitan waters, further south than previously recorded.

A new CURTIN University study investigating the complex evolution of two iconic Western Australian landmarks, has traced their transformation over thousands of years and offers a glimpse into their future.

Scientists lead call to end shark hunt.

On an isolated stretch of Western Australian beach, artist Tim Pearn creates art from colourful washed-up plastic waste

On an isolated stretch of Western Australian beach, artist Tim Pearn creates art from colourful washed-up plastic waste

A juvenile green sea turtle discovered floating in an estuary in Broome has been brought to Murdoch University's Animal Hospital for a CT scan.

Australia's best beaches: Perth's Cottesloe wins most votes in Guardian poll.

The extreme Western Australia 2011 marine heatwave had a lasting effect on the marine ecosystem and after 7 years, only parts of the ecosystem have showed good signs of recovery. After the heatwave, scallop fisheries in the Abrolhos Is. and Shark Bay were closed for 3-5 years, while the Shark Bay crab fishery was closed for 18 months; these fisheries at the center of the heatwave have shown some improvement due to better protection of spawning stock and improved environmental conditions. Also at the center of the heatwave, Roe's abalone suffered a catastrophic mortality and has not recovered as spawning stock remains very low. The Perth abalone stock which was outside the peak heatwave area had a major stock reduction but remained opened with reduced catches. The heatwave had a marked indirect effect on brown tiger prawns in Exmouth Gulf due to loss of seagrass habitat. The heatwave also resulted in a decline in western king prawn recruitment in Exmouth Gulf, to the north of heatwave center, but an improved recruitment in the cooler waters of Shark Bay. Western rock lobsters near the heatwave peak also appear to have been indirectly affected and have not recovered. Factors influencing the recovery rate from the heatwave appeared to be: species near their upper temperature range and/or sensitive to warming temperatures; spatial overlap between the warming event and species distribution; whether spawning stock was affected to the point of recruitment impairment; life-cycle duration of invertebrate (or habitat) species affected; and management intervention. This study provides a framework for managing the consequences of heatwaves on fisheries by highlighting the value of early identification of the event and its effect on fisheries and having flexible harvest strategies for early management intervention. This is particularly important as long-term increases in water temperatures will increase the frequency of marine heatwave events and the fisheries stocks would hav