Announcing the release of a new report which compares the two main models for modelling population consequences of noise on harbour porpoises – the DEPONS and Interim PCOD models!
The report was co-authored by Jacob Nabe-Nielsen (Aarhus University) and John Harwood (St Andrews University – with whom we’ve been working on the development of iPCoD and many PCoD projects) – the two architects behind the models respectively. The report compares two different frameworks to assess the potential effects of noise on harbour porpoise: Interim Population Consequences of Disturbance (iPCoD) and Disturbance Effects of Noise on the Harbour Porpoise Population in the North Sea (DEPONS). The report is the first of its kind and a crucial document to help scientists, regulators, developers and their consultants understand the similarities and differences between the models and where the big gaps in knowledge exist. The report states:
Although both models simulate population dynamics based on the birth and survival rates of individual animals, they model survival in a different way. iPCoD uses average survival rates derived from data from North Sea animals. In the DEPONS model, survival emerges from the individuals’ ability to continuously find food. In this report we compare the structure of the two models, and describe the data they require and the kinds of output they provide. We then identify key differences between the approaches and discuss how their outputs can be compared.
The structural differences between the two modelling frameworks make each model better suited to answer a different set of questions. These differences between the two models are likely to result in different predictions of the population effects of particular development scenarios, and a direct comparison of model predictions is only likely to be informative if input parameters are aligned and model outputs are carefully analysed.
Be sure to check out the report!
Here are links to some of our PCoD projects: