Marine Scotland Science has released a report on how seals use the water column in tidally energetic areas based on a case study conducted at the Brims tidal energy lease area.
The work, undertaken by the Sea Mammal Research Unit (SMRU) at the University of St Andrews, can be used to inform collision risk models on the risks posed between seals and tidal turbines, Marine Scotland said.
“As the tidal renewable industry continues to grow, increasing our understanding of the way that marine mammals use tidally energetic areas is of particular importance.
“This is a particular issue as there is increasing evidence that tidal energetic areas can be important foraging areas for marine mammals, therefore understanding how marine mammals use the water column is required to improve assessments of the risk of collision between seals and tidal turbines in highly energetic areas,” said Marine Scotland.
The report builds on previous work which resulted in the improvement of collision risk modeling approach, and presents a specific case study on how harbour and grey seals use the water column within the Brims tidal energy lease area, located between Orkney and the north coast of Scotland.
Summarizing the most up to date telemetry data from 20 seals tagged between 2010 and 2016, the report details the proportion of time seals spent at different depths in the water column, as well as the number of times seals passed through different water depths during foraging dives in the Brims site.
The Brims site is much deeper than the site used in the original work and so provides an opportunity to consider how this affects seals’ use of the water column, according to Marine Scotland