SRSL develop and deploy technologies for recording baseline underwater noise, device operational noise and installation noise (inc its propagation) in high-flow tidal energy environments. Our survey and modelling approaches are tried-and-tested in the Scottish EIA process.
SRSL first provide thorough desk-based reviews of existing data to include target species identification and initial risk assessment. Our teams have the expertise to design sea- and land-based survey methodologies appropriate to the proposed the site and development characteristics. This includes the use of visual and towed passive acoustic vessel-based surveys and shore-based seabird vantage point (VP) survey protocols for combined marine mammal and bird surveys. SRSL also deploy moored CPODs and drifting CPODs to assess high-resolution odontocete distribution in the development sites. All proposed survey methods will be fully discussed with the regulators and their conservation advisors on the proposed methods, as their consultation and agreement is essential prior to commencement of any survey work.
To determine the acoustic footprint of operational tidal turbines or the impact of other anthropogenic noise (e.g. piling), an understanding of the ambient background sound in the receiving environment is required. This will provide the baseline against which audibility for marine mammals can be calculated. SRSL specialise in the acoustic characterisation of sites and the operational noise of demonstration devices using the SRSL 'Drifting Ears' approach; a tried and tested method for measuring underwater noise in high-flow tidal environment.
The risk of collision between marine animals and tidal energy devices can be assessed by considering the behaviour and abundance of animals at risk in the location that devices are to be deployed, together with the characteristics of the turbines and the tidal regime. SRSL have developed an encounter risk model (ERM) which can be used to predict rates of encounter between animals with marine renewable energy devices. This is the first model of its type to be submitted in an EIA for a tidal energy development in Scotland (Meygen Ltd 2012).