SERPENT - Scientific and Environmental remotely operated vehicle (ROV) Partnership using Existing iNdustrial Technology. A highly successful mission resulted after 5 days of ROV operations. Eight video transects were completed, for megafaunal abundance, diversity and distribution in the area. Transects were conducted every 450m and extend to 100m from the drill site. Videos will be analysed for megafaunal diversity and habitat mapping during 2006.
There is only one habitat type at END01 which is soft bottom. There is no evidence of any rock formations or hard bottom of any type. This will be accounted for when analysing video transects. Preliminary analysis indicates a high density and diversity of megafauna. The main component of the megafaunal community is consistent with soft bottom communities and includes echinoderms (asteroids, echinoids) a host of crustaceans (prawns and large isopods), eels that live in the sediment and some bottom dwelling fish. Unlike at ENC03, there were no large sponge beds only sparsely scattered sponges.
A variety of prawns, crabs, hagfish, amphipods, isopods and fish were attracted to the bait traps (first experiment). Initial examination of the data suggests that there is a difference in the diversity of organisms that visit the traps (inside vs outside the drill spoil). Isopods and hagfish only appeared to visit traps outside of the drill spoil. Further analysis will validate any trends in the data.
Species collected for determining the level of heat shock protein expression (second experiment):
* 5 isopods outside of the drill spoil
* 5 isopods outside of the drill spoil re-deployed within the drill spoil
* 5 isopods outside of the drill spoil re-deployed outside of the drill spoil
* 5 isopods outside of the drill spoil caged and attached to ROV garage, immersed to seabed and brought to surface again
* 23 isopods outside of the drill spoil
* 20 isopods outside of the spoil used for re-deployment experiment
* 40 shrimp outside of the drill spoil
* 57 amphipods outside of the drill spoil
* 3 hagfish outside of the drill spoil
* 20 shrimp within the drill spoil
* 8 amphipods within the drill spoil
* 1 sea cucumber within the drill spoil
Statement: END02 is approximately 13 m away from END01 so there was some overlap in drill spoil.
Baited traps were deployed both within and outside of the drill spoil to attract mobile megafauna. Traps were examined every 24 hrs and video taped for 5 minutes. Large numbers of shrimp were seen on this mission whereas previous missions in this field failed to collect shrimp. Shrimp and amphipods from within the spoil (8m from blow-out converter (BOP)) and shrimp, amphipods, hagfish and isopods outside of the spoil (100 m from BOP) were collected for heat shock protein analysis. Traps were re-deployed every 24 hrs and collection repeated. In a second experiment, isopods outside of the spoil (100m from BOP) were collected and re-deployed within the drill spoil and outside of the drill spoil. Controls were brought to the surface and frozen and procedural controls were re-immersed down to the sea bed (attached to back of ROV garage) and brought back to surface.
Woodside Energy Ltd
Katie Robertson, The University of Sydney (USYD)
The science goals for this project are to expand on baseline environmental surveys carried out in the area on behalf of Woodside. We conducted detailed ROV megafaunal video surveys to provide quantitative data on megafaunal ecology; particularly abundance, diversity and distribution in this area. In addition we conducted a series of experiments to quantify the expression of heat shock proteins on deep sea organisms from within and outside of drill spoil including an in situ deployment to determine the effects of drilling mud on heat shock protein expression.