Britain’s whale, dolphin and seal populations are at risk because of inconsistent approaches to environmental impact studies, experts have found.

Researchers from the Edinburgh-based Heriot-Watt University examined 93 "cumulative effect assessments" conducted by 11 maritime industries between 2009-2019.

Industries are obligated to conduct these assessments during the planning process of new projects - such as offshore wind farms, fish farms, harbour developments or turbines.

They attempt to assess whether the projects will have increasing negative effects on the environment, and the animals within it.

Experts found that some of these studies were extremely vague, while others contained extensive scientific detail into the project's environmental impact.

Surveys conducted by fish farms, oil and gas field developments, harbour development projects, and decommissioning scored the lowest, and did not show signs of improvement, according to the research.

Newer industries like offshore wind farms and tidal and wave energy performed better, showing improving signs over time.

These differences could be leading to negative consequences for the UK’s maritime animals, according to Professor Lauren McWhinnie.

She said: “Human activity with UK waters could influence how whales, dolphins, seals and other marine animals use these areas.

“Changes to their habitats can have temporary or permanent effects on these animals, depending on the nature of the activity.

“In some instances, this could even lead to population-level impacts.

“Ideally all marine users would assess their activities based on the same standard.

“This would help safeguard marine mammals and the wider marine environment.

“This is just one measure we could put in place to help ensure that further development of our marine space is done so in a sustainable manner, prioritising the conservation of important species like whales and dolphins around our coast.”

Marine animals found in Wales include porpoises, bottlenose dolphins, grey seals and leatherback turtles.

Basking sharks can sometimes be spotted off the Pembrokeshire coast, and Orcas (killer whales) occasionally visit the waters of north Wales.

North Wales Chronicle: Killer whales are sometimes spotted off the Welsh coast. (Picture: Pixabay)Killer whales are sometimes spotted off the Welsh coast. (Picture: Pixabay)

The bizarre looking Ocean Sunfish - which can reach the same weight as a car - has been sighted in Mumbles, Langland and Milford Haven in recent years.

PhD student Emily Hague said: “We scored the 11 industries over time based on how they are assessing their potential to have cumulative impacts on marine mammals.

“What’s striking is the disparity between these legally-required assessments.

“Some cumulative effect assessments were just a few lines in a report, while others were 50 pages long, including complex and up-to-date and appropriate scientific knowledge and methodology.

“We found that cumulative effect assessments conducted by fish farms, harbour development projects, oil and gas field development and decommissioning scored the lowest.

“According to our criteria, these industries showed no improvement over time.

“Newer industries like offshore wind farms and tidal and wave energy performed much better and improved over time.”