The research undertaken by ABPmer and SMRU Consulting has presented improved assessments of the risk of collision between harbour seals and tidal turbines using the most up to date information available on how harbour seals use tidally active areas.
The aim of this research project, commissioned by Marine Scotland and Scottish Natural Heritage, was to provide improved assessments of the level of mortality to harbour seals potentially caused by tidal turbines in the Pentland Firth and Orkney Waters region, using recently available information from a number of areas of work.
Building on work undertaken in a previous project, this research has further developed the modelling approach utilising additional information on observed seal behaviour patterns derived from targeted telemetry tracking studies, such as dive depth profiles and transit speeds, and device specific information on the shape of the turbine rotor.
It also considered the relationships between tidal current, rotor speed and the risk of a collision being fatal.
The updated model produced through this work was applied to two tidal energy projects in the Pentland and Orkney Water region, more specifically, to the MeyGen Phase 1A array of four turbines at the Inner Sound in the Pentland Firth, and the multi-berth European Marine Energy Centre (EMEC) tidal test site at the Fall of Warness, Orkney.
As part of its demonstration strategy for tidal energy, Marine Scotland is funding further research, which will deploy sophisticated combinations of underwater instruments such as active sonar devices, acoustic monitoring, video cameras and seal tagging, to observe the interactions between tidal turbines and a range of animals, including harbour seals and other marine mammals, at an operational tidal array.