Abstract
Windfarm construction can impact marine mammals primarily as a result of the underwater noise generated by the installation of the foundation. Mitigation is available to prevent death and injury, but the wider constructions of disturbance is unclear. Potential consequences for extended or repeated disturbance for marine mammals include behavioural and physiological changes that can affect the health and vital rates of the individual animals which then could translate to population effects. There are two major clusters of windfarm development on the Scottish east coast. The Moray Firth has already seen the construction of the Beatrice Offshore wind farm this year and Moray East is progressing to build out. Other applications are anticipated and consented, leaving a question as to how cumulative impact assessment will be undertaken. These major developments, with hundreds of large offshore wind turbines, individually have the potential to input construction noise over tens of kilometres and taken cumulatively, potentially over a number of years for each project. Cumulative assessment of these projects is difficult. Each developer is required to consider the impact of their development in conjunction with all other developments (consented and proposed). Whilst we (SNH) have advised consistency in methods, often this is not realized, due to differing timeframes for submission and reluctance to share data due to commercial sensitivities. This means that the cumulative assessment is not always done consistently, which results in variable conclusions.
This project will assess cumulative assessment in an independent and as consistent an approach as is possible with the available data. Currently the only tool available to consider cumulative impact from disturbance is the Interim PCoD model developed by SMRU. This paper focusses on the cumulative potential population impacts to bottlenose dolphin (Moray Firth SAC) and grey seal (Isle of May SAC)