Scientists at the Australian Institute of Marine Science (AIMS) have recently published groundbreaking research on the environmental impact of offshore oil and gas infrastructure in Australia’s south-east and north-west regions.
The studies, conducted in collaboration with Deakin University and ORCAS Consulting, reveal that these structures play a minor role in maintaining regional populations of marine life.
The research, published in two separate journal articles, focused on the concept of connectivity — a crucial process for the long-term resilience of fish and invertebrate populations.
While it’s known that oil and gas infrastructure can host diverse marine life, the studies aimed to determine the importance of these structures for population persistence.
Dr Di McLean, an AIMS principal research scientist and co-author of one of the papers, emphasised the critical nature of this research as more oil and gas structures require decommissioning.
“There is evidence that oil and gas structures can increase the local abundance and diversity of marine organisms, particularly in seascapes where natural habitats are scarce,” Dr McLean stated.
The Bass Strait study, published in Science of the Total Environment, examined five representative species, including three rocky reef fish and two invertebrates.
The research found that while platforms played a minor role in supporting these species’ long-term health and survival, subsea pipelines facilitated important dispersal processes in their early life stages.
Interestingly, the study revealed that platforms were a modest source of connectivity for the jewel anemone, despite its dominance on these structures.
However, for other species studied, platforms were not significant as destinations or stepping-stone habitats.
In contrast, the north-west study, published in Marine Pollution Bulletin, focused on two fish species and a coral.
This research found that oil and gas platforms and subsea wells do not significantly impact the dispersal and persistence of these species.
Natural reefs in the system were identified as the primary sources of fish and invertebrate larvae.
Dr Ronen Galaiduk, an AIMS research scientist and co-author of both papers, highlighted the critical role of natural habitats.
“The natural rocky reefs in the Bass Strait and tropical reefs in the north-west were critical sources, destinations and promoted local-scale connectivity for all of the species studied,” he explained.
The researchers recommend that decisions regarding the removal of offshore infrastructure should be made on a case-by-case basis, considering the contributions of pipelines to regional connectivity processes.
This research provides valuable insights for policymakers and industry stakeholders as they navigate the complex process of decommissioning offshore oil and gas infrastructure.
By understanding the ecological role of these structures, more informed decisions can be made to balance environmental conservation with industrial needs in Australia’s marine ecosystems.
