OSC is pleased to announce publication of our article Characterising the second wave of fish and invertebrate colonisation of an offshore petroleum platform (Todd et al., 2021) in the scientific peer-reviewed journal ICES Journal of Marine Science. This article, led by OSC’s Managing Director (MD), Dr Victoria Todd, was co-authored by several other OSC staff and two Australian researchers with whom OSC has collaborated previously – Professor Peter Macreadie, Head of Deakin University’s Blue Carbon Lab, and Dr Dianne McLean, Fish Ecologist at the Australian Institute of Marine Science (AIMS).
As the North Sea’s Oil & Gas (O&G) reserves become depleted, an important decision has to be made about the fate of the giant rigs and thousands of kilometres of pipelines that have supported the industry for the past >100 years. The North Sea has 840,000 tonnes of material to be decommissioned, which is estimated to cost £40 billion by 2040. Current policy (OSPAR Decision 98/3) requires that this infrastructure is removed from the seafloor, but a recent global survey found that 94.7% of environmental experts agreed that a more flexible case-by-case approach to decommissioning could benefit the North Sea environment (Fowler et al., 2018). To help guide decommissioning decisions in the North Sea, there is urgent need for information on the habitat value of offshore infrastructure, particularly for fish and invertebrates.
Using video footage opportunistically obtained from industrial Remotely Operated Vehicles (ROVs), Todd et al. (2021) investigated colonisation of the jacket of a North Sea O&G platform 1–2 years after its initial construction in 2015. Compared to baseline communities (pre-construction) and the first wave of pioneering colonisers a few days after construction (Todd et al., 2020), we documented 48 additional taxa, including a rare sighting of a pompano (Trachinotus ovatus). The second wave of motile colonisers presented greater diversity than the pioneering community. Occurrence of species became more even over the two years following installation, with species occurring in more comparable abundances. No sessile taxa were recorded on the new jacket during first-wave investigations; however, 17 sessile species were detected after 1 year (decreasing to 16 after 2), with species richness expected to increase further with time. Motile species were found to favour structurally complex, sheltered sections of the jacket (e.g. mudmat, a seabed ‘mat’ preventing structures from sinking), while sessile organisms favoured exposed elements. Moreover, evidence of on-jacket reproduction was found for two commercially important invertebrate species, namely common whelk (Buccinum undatum) and European squid (Loligo vulgaris).
Overall, this study demonstrates that offshore platforms have capacity to develop into diverse, highly productive systems. These findings may have implications for decommissioning and resource management strategies, suggesting that a case-by-case reviewing approach should be favoured over the most common ‘one size fits all’.
Fowler, A.M., Jørgensen, A.-M., Svendsen, J.C., Macreadie, P.I., Jones, D.O., Boon, A.R., Booth, D.J., Brabant, R., Callahan, E., Claisse, J.T., Dahlgren, T.G., Degraer, S., Dokken, Q.R., Gill, A.B., Johns, D.G., Leewis, R.J., Lindeboom, H.J., Linden, O., May, R., Murk, A.J., Ottersen, G., Schroeder, D.M., Shastri, S.M., Teilmann, J., Todd, V.L.G., Van Hoey, G., Vanaverbeke, J., and Coolen, J.W. (2018): Environmental benefits of leaving offshore infrastructure in the ocean. Frontiers in Ecology and the Environment 16, 571-578.
Todd, V.L.G., Williamson, L.D., Cox, S.E., Todd, I.B., and Macreadie, P.I. (2020): Characterising the first wave of fish and invertebrate colonisation on a new offshore petroleum platform. ICES Journal of Marine Science 77, 1127-1136.
Todd, V.L.G., Susini, I., Williamson, L.D., Todd, I.B., McLean, D.L., and Macreadie, P.I. (2021): Characterising the second wave of fish and invertebrate colonisation and production potential of an offshore petroleum platform. ICES Journal of Marine Science In Press, fsaa245.