Research Voyages

The 27-day voyage started from Cairns on February 23 and will finish at Weipa on March 21.

The marine National Facility RV Southern Surveyor has been chartered by CSIRO, Geoscience Australia and the National Oceans Office for a three-phase assessment of seabed habitats in the Gulf of Carpentaria and Arafura Sea.

The first voyage is a CSIRO-led investigation into the effects of trawling on the seabed habitats and biodiversity in the southern gulf, a productive region for the Northern Prawn Fishery (NPF). The vessel departed from Cairns on February 23 and will end its 27-day journey at Weipa on March 21.

Chief scientist on the voyage is Dr Peter Rothlisberg, and the principal investigator for the associated research project is Dr Rodrigo Bustamante. They will lead the sampling activities of 14 scientific and technical staff.

The scientists – from CSIRO, Geoscience Australia and Griffith University–will sample seabed habitats at prawn fishing grounds near Groote Eylandt, the Sir Edward Pellew Group and Mornington Island.

They will trace the physical and biological processes that sustain 'soft' seabed communities at 120–150 sampling stations in four different regions and habitat types, and compare areas subject to different historical levels of trawling.

The sediments will be sampled with a 'box corer' to analyse their physical characteristics, ecological processes and resident macrofauna; a prawn net, sled and remote-operated underwater video camera will be used to sample fish and invertebrate communities. Water properties including current strength and direction, temperature, salinity, and productivity also will be measured.

Southern Surveyor voyage track.

Information gathered on the voyage will form the basis of a multi-disciplinary study of seabed communities and ecosystem processes in trawled and untrawled areas of the gulf that will quantify the effects of commercial fishing.

This study has been made possible through the availability of detailed patterns of fishing activity recorded for the management of the NPF, and the advanced sampling capabilities of the RV Southern Surveyor.

It will provide knowledge of and tools for evaluating seabed habitats and communities – such as computer-based models of marine food webs and seabed maps – and lead to strategies for managing the effects of prawn trawling to support the sustainability of the NPF.

For example, management strategy evaluation tools based on the new information will be used to compare alternative spatial management scenarios for the NPF, and enable environmental, economic and stock-management objectives to be combined.

Knowledge of the distribution of habitat types across these waters, and their responses to different patterns of use, also will contribute to Australian Government bioregionalisation and conservation processes and to the regional marine plan for northern waters between Torres Strait and the eastern Arafura Sea.

The second voyage of the joint charter will focus on hard-bottom habitats and untrawled rocky reefs in the southern gulf and the third will inspect hydrocarbon seeps in the eastern Arafura Sea and their associated biodiversity.