Vibro piling effects on harbour porpoises

Vibro piling versus regular piling

Vibratory hammers used in vibro piling function differently from ordinary impact pile drivers. Instead of hard blows at intervals, the piles are struck with less force where intervals are much shorter or even absent. The piles can be said to be vibrated into the ground. A vibratory hammer strikes with less energy so the sound produced by striking a pile is also less loud and the frequency composition is different to that of regular piling. As a result, the effects on the hearing, behaviour and health of porpoises and other marine mammals may also be different from traditional pile drivers. Until now, the main focus has been on the disturbance caused by pile driving noise, this disturbance-unit is the unit the Dutch government uses to determine the impact on the population of the harbour porpoise employing the model iPCoD. However, for noise of a different nature, like vibro piling, the type and magnitude of the effects are largely unknown. It is therefore important to determine the behavioural threshold (disturbance threshold) and the hearing thresholds (TTS & PTS) for this new sound source.

Cooperation

The research will be done by the Marine Biological Research Center at University of Southern Denmark, located adjacent to the Danish Fjord&Baelt Centre keeping harbour porpoises.

This project is contracted to the University of Southern Denmark (USD) and Fjord&Baelt Centre Kerteminde Denmark. An advisory board with experts from the US National Marine Mammal Foundation and Aarhus University will provide scientific quality control throughout the project. It is commissioned by the Rijkswaterstaat Offshore Ecological Research Programme (Wozep) on behalf of the Ministry of Climate Policy and Green Growth (KGG).

More information

See for more information the website of the Marine Biological Research Centre or Fjord&Baelt.

Please contact the Wozep team if you have additional questions by filling out this form.