Sonar data show seal presence fell 77% near active Scottish tidal turbine rotors

Local marine life safety is at risk as underwater tidal turbines become more popular.

Scotland is experimenting with innovative ways to boost its renewable energy footprint.

Offshore clean power generation has been highly beneficial, but alternative technologies are key to meeting urgent climate targets.

Society’s modernization has led to an unprecedented rise in electricity consumption across residential, industrial, and commercial sectors.

As interest in Scottish tidal currents grows, it is vital to establish potential ecological impacts first.

Will native marine mammals exhibit altered behavior near these unconventional turbines?

How Scotland is prioritizing a greener footprint

Old habits are hard to break, especially when they have occurred over many generations.

Scotland exemplifies this with its long history of fossil fuel reliance.

It shaped the nation’s economy and daily life, as coal and oil were the primary drivers of industrial growth.

Later on, natural gas from the North Sea became a core pillar of domestic energy generation.

While this has raised climate concerns, this deep-seated dependency remains difficult to break today.

Society’s modernization has led to an unprecedented rise in electricity consumption across residential, industrial, and commercial sectors.

Currently, the total Scottish carbon footprint is roughly 61 million tonnes of carbon dioxide equivalent annually.

To break this carbon-heavy reliance once and for all while meeting rising energy demands, renewable energy sources are being prioritized.

This is essential in reaching net-zero by 2045, with an interim target of a 90% reduction in emissions by 2040.

Offshore generation has become strategic

Scotland has some of the most pristine natural landscapes in the world, entrenched with centuries of history.

To ensure the preservation of nature and culturally significant sites, developers are increasingly opting for offshore power generation.

Offshore wind power has become particularly vital for Scotland’s energy strategy.

Strong, consistent coastal winds help meet rising power demand while accelerating progress in meeting climate ambitions.

It has also helped secure significant deals with major companies like Amazon.

However, wind generation remains inherently intermittent, regardless of where it is harnessed.

This results from accelerated climate change altering global weather patterns.

Since wind fluctuations are more volatile, grid operators need complementary electricity-generating sources for stability.

This has driven interest in alternative offshore technologies that deliver predictable power.

Tidal currents are becoming popular in this category, as they offer consistent, predictable energy driven by the pull of the moon.

But more research is needed on the technology’s impact on marine wildlife.

Monitoring seal behavior near tidal turbines

Tidal turbines may offer predictable power, but how ocean animals respond to the technology remains unpredictable.

That is why researchers from the University of St Andrews tracked an operational tidal turbine in Pentland Firth, Scotland.

The study focused on local harbor seal activity over one year using advanced multibeam imaging sonar.

During this time, 704 close-range seal encounters were recorded near the active underwater turbine.

Discovering fluctuations in seal presence based on key factors

Environmental conditions and current speeds played a role in seal presence near the turbine.

The animal naturally avoided the area during the following:

• At night
• Peak flow speeds
• Throughout the winter months

Additionally, high flow speeds of 5.1 mph or faster resulted in a 77% drop in presence around the rotor site.

These findings demonstrate that harbor seals actually detect active tidal turbines.

The seals then exhibit localized avoidance behaviors, which lower blade strike risks.

The research provides fundamental insights for future tidal turbine projects off Scotland’s coast.

By understanding how local mammals like seals adapt to the presence of underwater technologies, developers can map safe deployment zones.

However, it is crucial to continue additional monitoring, as not all species are likely to exhibit the same avoidance behaviors.

Ultimately, Scotland can successfully harness tidal energy if responsible monitoring and management protocols are taken.

You can review the study using: Montabaranom, J., Gillespie, D., Longden, E., Rapson, K., Holoborodko, A., Sparling, C., & Hastie, G. (2025). Seals exhibit localised avoidance of operational tidal turbines. Journal of Applied Ecology, 62(2), 242-252.