Impacts of windfarm construction on harbor porpoises

This type of noise is increasingly prevalent due to the high demand for green energy, and currently there are >900 offshore wind farms at various stages of development in Europe alone. Porpoises are strictly protected in European waters, so assessing the impacts of construction noise is critical for regulators. We demonstrate how the framework can be used for spatial planning to partly mitigate population impacts of disturbances.

The model -- named DEPONS -- builds directly on how disturbances influence animal movements, foraging and energetics, and is therefore applicable to a wide range of species. To demonstrate the model, the impact of wind farm construction noise on the North Sea harbor porpoise population was assesed. The scientists monitored the population density during construction of Gemini, a Dutch offshore wind farm, by recording the echolocation sounds that porpoises use for navigating. Afterwards a virtual Gemini landscape where wind turbines were built in the same order, and generating the same amount of noise, as in the wind farm where porpoises had been monitored. This landscape was used for running scenarios in the model.