SMRU Consulting Europe – collaborating with a team of researchers at the University of St Andrews, led by Prof. John Harwood – have developed an interim framework for assessing the consequences of noise disturbance on marine mammal populations that may result from the underwater noise generated by offshore renewable energy developments (Population Consequences of Disturbance PCoD).

The Interim PCoD framework project was commissioned and jointly funded by The Crown Estate, Marine Scotland Science, the Joint Nature Conservation Committee, The Department for Energy & Climate Change, Natural Resources Wales, Natural England and Scottish Natural Heritage.  Members of each regulatory and statutory nature conservation body, along with developer representatives, participated in a steering committee for the project to ensure that the model met their needs.  The framework is underpinned by a study of The Sensitivity of UK Marine Mammal Populations to Marine Renewables Developments (Harwood & King 2014) that was funded by the Natural Environment Research Council as part of its Marine Renewable Energy Knowledge Exchange programme.

The potential risk of injury and/or disturbance to marine mammals during construction of offshore renewable energy developments has been identified as a key consenting risk for projects in UK waters.  Possible consequences of exposure to underwater noise from piling include: disturbance that could cause marine mammals to either move away or change behaviour, suffer temporary hearing damage or permanent physical injury. The interim PCoD model assesses what the longer term and larger scale impacts of these consequences are to the exposed group(s) of animals as a whole.

The basic PCoD approach was developed by an international group of experts in the US Office of Naval Research Working Group on the Population Consequences of Acoustic Disturbance US National Research Council’s Committee on Characterizing Biologically Significant Marine Mammal Behaviour in its 2005 report. Their work provided the foundation for the Interim PCoD framework, which was developed at a workshop on Assessing the Risks to Marine Mammal Populations from Renewable Energy Devices, which was jointly funded by Countryside Council for Wales (now Natural Resources Wales), the Joint Nature Conservation Committee and the Natural Environment Research Centre.

Interim Model: This model, written in R, is a protocol for implementing an interim version of the PCoD approach for assessing and quantifying the potential consequences for marine mammal populations of any disturbance and/or injury that may result from offshore energy developments. It has been designed to use the kinds of information that are likely to be provided by developers in their Environmental Statements and Habitats Regulations Assessments.
We emphasise the interim nature of this approach, which was developed to deal with the current situation, where there are limited data on the way in which changes in behaviour and hearing sensitivity may affect the ability of individual marine mammals to survive and to reproduce.


The Interim PCoD report can be downloaded from here and the PCoD model software can be downloaded here.

The reports from the PCoD Lite project working with the US Navy can be downloaded here (final project report) and here (application report).

The Population Consequences of Acoustic Disturbance (PCAD) framework developed by the National Research Council’s panel on the biologically significant effects of noise. After Fig. 3.1 in National Research Council (2005). The number of + signs indicates the panel’s evaluation of the level of scientific knowledge about the links between boxes, 0 indicates no knowledge.