Cutting off shore wind farm noise helps sea life
WWF-backed research finds big benefits for porpoise populations can be achieved through cost-effective offshore wind farm noise reduction methods
Highly effective measures can be taken to “hugely reduce” the underwater noise impact from offshore wind farms on harbour porpoise populations, according to a new WWF-UK-backed study.
Environmentalists have previously voiced fears that the noise from the construction and operation of offshore wind farms can negatively impact porpoises, dolphins, and some other marine animals.
Some experts have warned high levels of underwater noise can cause injury or even death to harbour porpoises, although it is more common for such animals to change their behaviour to avoid harbour areas with even low levels of noise, potentially leading to porpoises abandoning large areas for weeks or months.
However, new research published on Friday by WWF and conducted by marine mammal consultancy SMRU Consulting assessed how measures designed to curb noise from offshore wind farms could help minimise the impact on porpoise populations.
According to the study, noise reduction has significant benefits for harbour porpoises, with even a slight lowering of construction noise levels of around eight decibels potentially vastly improving – by around 96 per cent – the chances of stemming a possible annual one per cent decline in North Sea porpoise populations.
Alec Taylor, WWF-UK’s marine governance programme manager, said the report showed there were big benefits to wildlife from easily-achievable and cost-effective noise reduction measures.
“As we move towards a zero-carbon future, we must take the right steps to allow the maximum deployment of renewable energy at minimal cost to biodiversity,” he said. “The expansion of wind power around our coastline is great news, but there will need to be some form of mitigation for harbour porpoises, which are acutely sensitive to noise. It’s therefore vital for both scientists and developers to know how reducing noise by different levels benefits porpoises, so that mitigation can be cost-effective.”
The report is based on the results of tested technology and “allows for potentially more challenging UK conditions”, according to WWF.
Measures that can be taken to reduce noise underwater include altering piling schedules, air-filled tubes, hydro-sound dampeners, or bubble curtains – a technique which produces bubbles that act as a barrier against underwater soundwaves.
Last month, DONG Energy was given the go-ahead for its Hornsea 2 wind farm off the coast of Yorkshire, providing certain conditions are met to mitigate the disturbance of local porpoise populations during development.