Scientists from CSIRO, the California Institute of Technology, and Woods Hole Oceanographic Institute have surveyed to 3000 m in the new Tasman Fracture Zone Commonwealth Marine reserve.  Hard corals were found as deep as 2300 m and soft corals as deep as they went. 

The Autonomous Benthic Explorer (ABE), an un-manned submersible, was used to photograph and survey marine features at depths to 3000 m - well over a kilometre deeper than has previously been studied in Australian waters.  The ABE was deployed on six missions during a three-week cruise on the Southern Surveyor, reaching depths of 2960 m and taking over 6000 photographs of the sea floor.  The photographs are still being analysed in detail, but they already indicate sites from which fossil and sub-fossil corals can be collected for paleo-oceanographic and climate reconstruction (a primary objective of the missions) and show a rich benthic community well beyond depths expected.  Soft-corals, in a variety of taxa, were found as deep as ABE could dive, living in complete darkness and at temperatures of 1-2º. 

Over 1500 coral samples were obtained from shallower depths (1000-1500 m), using dredges, to start analysing the age and growth of the reefs and begin paleo-climate analysis. 

Samples were also collected for genetic connectivity studies in the CERF Hub.  More samples, from greater depths, will be collected on a follow-up cruise in December 2008 using the US deep-sea vehicle, Jason.  It is expected that Jason will sample to at least 4500 m, extending even further our information on biodiversity in these marine reserves.

Media release and images: http://www.csiro.au/news/AncientClimateSecrets.html