Recruitment to the western rock lobster fishery has been recognised to be largely driven by environmental conditions but the role of freshwater and/or contaminant derived from submarine groundwater discharge (SGD) from land is unknown. Freshwater discharge has been shown to be positively correlated with crab larval abundance and there is anecdotal evidence to suggest that settlement hotspots for a range of rock lobster species are often associated with freshwater discharge and water-borne chemical signals. Potential contaminants in SGD may also impact lobster populations. This investment will identify significant SGD near established western rock lobster settlement monitoring sites and establish the direct and indirect impacts of SGD on lobster populations including the contribution to seagrass beds and the possible impact of contaminants in SGD.