There is a regulatory need to determine whether the deployment of Marine Energy Conversion Systems (MECS) is likely to have any significant effect on site integrity. An important part of this is to identify whether MECS have any impact on the abundance or distribution of wildlife species in the vicinity of such devices. Using information collected at the European Marine Energy Centre (EMEC) grid-connected wave and tidal test sites, EMEC is leading an in-depth analysis of landbased wildlife observations data with respect to the operational status of different devices. This data analysis project brings in expertise from the Centre for Ecological and Environmental Modelling (CREEM) in the application of the statistical package MRSea to quantify any spatially-explicit change attributable to MECS testing. This paper summarises progress to date, with particular emphasis on the methodology applied to perform the analysis of the test site observations with respect to the potential displacement of key wildlife species.