Dr Brendan Brooke, Geoscience Australia 
Leader - CERF Surrogates Program 

Surveys have now been successfully completed at the Lord Howe Shelf, South-East Tasmanian Shelf, Carnarvon Shelf and Jervis Bay. These areas were selected as they provide good examples of major types of benthic habitats found in the different bioregions. The data and samples collected will be used to test, at fine spatial scales, the utility of several physical variables as surrogates for patterns of benthic biodiversity.

The recently completed Carnarvon Shelf survey was undertaken by staff from Geoscience Australia and the Australian Institute of Marine Science aboard their new research vessel RV Solander. The vessel proved a highly suitable platform for shallow-water multibeam mapping and seabed sampling and a key dataset for our surrogacy research was acquired.

Despite often challenging sea conditions, approximately 1,000 square kilometres of the Carnarvon Shelf was mapped with GA’s 300 kHz Simrad mulitbeam system – around half a terabyte of seabed data. Towed underwater video, still photographs, and seabed sediment samples were collected at 120 sample stations, acoustic sediment profiles were collected across the shelf and upper slope and current-meter data was collected on the inner and middle shelf.

The Carnarvon Survey is well-integrated with the established Ningaloo environmental research program being run by the Western Australian Marine Science Institute (WAMSI), with CERF sampling designed to complement existing video and sample data collected by AIMS and made available to CERF. The new CERF data extends the Ningaloo database across the continental shelf and the combined datasets will better enable both CERF surrogacy research and WAMSI’s ongoing habitat characterisation.

As well as representing a major milestone for the CERF Marine Biodiversity Hub, the research results will be made available to managers of the West Australian and Commonwealth Marine Parks to better identify the distribution of marine habitats in this unique area of high biodiversity.

Images: 

Cowfish – sample collected in Pt Cloates survey area, Ningaloo. 

Pt Cloates: 10m (red) – 70m (blue) water depth, highly irregular seabed with coral bommies (10 – 20m tall) across the inner shelf outboard of the fringing reef. Data collected on RV Solander with a Simrad EM3002 (300 kHz) multibeam sonar system.