UNDERWATER renewables pose no long-term threat to wildlife, a new study claims.

A review of ten years of analysis on the impact of wave and tidal devices around Orkney has found they have “little impact” on populations of marine mammals and seabirds.

Energy converters were first installed at two island-side test facilities run by the European Marine Energy Centre (EMEC) in 2005.

Scottish Natural Heritage (SNH), EMEC and Marine Scotland have now examined ten years of observation records about the bird and mammal life living in and around the test areas.

The material, spanning around 10,000 hours of work at the Fall of Warness test site of Eday, found cormorants, guillemots, ducks, geese, shags and great northern divers moved when construction work started.Similar results were found with seals, whales and dolphins.

However, numbers recovered to around previous levels once installation finished and the turbines were operational.

Meanwhile, 6,500 hours of observation at the Billia Croo site near Stromness found “no significant changes” in the distribution or birds of mammals.

George Lees of SNH, said: “These initial results are reassuring and show that the deployment and testing of multiple wave and tidal energy converters in the seas off Orkney over more than a decade has not had a significant impact on the diverse and abundant wildlife living there.”

Now in its fourteenth year, EMEC is the world’s leading wave and tidal energy test site. Full-scale prototypes are installed and connected to the grid.

More marine energy converters have been put to work there than at any other facility around the world, with companies from ten countries testing 30 devices.

However, there have long been fears that the emerging technology could have detrimental effects on wild populations both above and below the waters.

Commenting on the publication, Caitlin Long of EMEC, who conducted the research, said the findings should help shape future planning and legislation.

She said: “The culmination of the extensive wildlife observation programme and this statistical analysis project should aid regulators, advisory bodies and developers in assessing the potential environmental effects of deploying such devices in our precious marine environment.

“This project begins to address one of the key unanswered questions regarding the evidence for, and potential extent of, species disturbance and displacement associated with wave and tidal device deployment.

“We at EMEC are keen to encourage the industry to build upon this initial work through further collaborative and coordinated research, utilising the facilities at our test sites to learn more about the marine environment which we share with a wonderful array of species in Orkney.”

Welcoming the report, which was published yesterday, Environment Secretary Roseanna Cunningham said: “Renewable energy devices operating at the European Marine Energy Centre have had little impact on the rich and diverse range of wildlife found in the waters around Orkney.

“This is an important step forward and strengthens our understanding of how marine mammals and seabirds respond to the installation and operation of wave and tidal turbines.

“We will continue to work with SNH to understand how this research can benefit the development of a successful and sustainable offshore renewable energy industry, while protecting our precious marine environment and iconic marine species.”