Could Leakage from Sub-sea Storage of CO2 Affect Marine Invertebrate Behaviour?

There is ongoing technological development of methods to detect and accurately measure CO2 seepage from sub-sea geological storage. This present research, aims to provide important information for interpretation of such data to enhance its value with respect to determining potential impacts from leakages on marine invertebrates that live in association with the sea bed overlying these storage areas. The research evaluates the potential effects of CO2 seepage on the behavioural responses of the bivalve mollusc Arctica islandica. A key step in this process is the establishment of threshold responses of the test organisms to indicate whether leakage events will have a serious impact on marine fauna both close to and more distant from a leakage source. The behavioural endpoints examined are high level biological processes such that significant alteration away from normal predictable patterns would indicate an ecologically significant change. An established exposure system was used to deliver a stepwise increasing volume of CO2 gas into a header tank system which in turn fed the exposure arenas. Measurement systems designed and built on site were used to continuously record key behavioural changes in the bivalves throughout the test exposures.