Strategies for obtaining ecological data to enhance decommissioning assessments

Abstract

Many offshore oil and gas platforms around the globe are reaching their end-of-life and will require decommissioning in the next few decades. Knowledge on the ecology of offshore platforms and their ecological role within a regional context in Australia is limited and the subsequent consequences of decommissioning remain poorly understood. Remotely operated vehicle (ROV) video is often collected during standard industry operations and may provide insight into the marine life associating with offshore platforms; however, the utility of this video for scientific purposes remains unclear. We propose a standardised method of analysing this large database of archival ROV footage with specific interest in analysing the vertical distribution of fish species. Baited remote underwater video systems (BRUVS) are a widely used tool for studying marine faunal communities, and we demonstrate the value of BRUVS for understanding the regional ecology around offshore platforms. A combination of BRUVS and ROV data can be used to determine the relative ecological value of offshore platforms within a regional context. The Wandoo oil platform on Australia’s North West Shelf was used as a case study to test these proposed methods by assessing demersal and pelagic fish populations both on and around the Wandoo platform and various natural habitats in the region.