Research by the University of Western Australia (UWA) on a BHP subsea oil and gas pipeline off the north-west coast of Australia has found that the pipeline is attracting roughly two to three times the commercial value of fish than its surrounding deep water areas.
In collaboration with BHP, the UWA researchers implemented specialised baited cameras to compare the diversity, abundance and size of fish around the 42.3-kilometre subsea pipeline and its surrounding habitat.
The study found that the pipeline which extends from the shallows to depths of greater than 140 metres had 131 species recorded on it, including the critically endangered Green Sawfish.
The researchers found that in depths over 80 metres, the pipeline held two to three times the value of commercial fish species than surrounding habitats, including high numbers of Goldband Snapper, Saddletail Snapper and Moses’ Snapper.
Similar fish numbers were observed off the pipeline in depths less than 40 metres as well.
UWA lead author and PhD student Todd Bond said the study showed that depth of the pipeline and availability of habitat in adjacent areas are important features defining differences in the fish community.
“We see a greater difference in the fish on and off the pipeline in deeper water, where their naturally occurring complex habitat becomes limited,” Mr Bond said.
“It is important we understand the interaction between pipelines and local fisheries to inform future decisions around how they are managed.”
“Hundreds of offshore oil and gas fields in the Asia Pacific will reach the end of their productive life over the next decade. Knowledge of the ecosystems supported by subsea infrastructure will help ensure that these assets are decommissioned in the way that maximises the benefit to the community and environment,” he commented.