Abstract
Environmental impact assessment evaluating consequences for harbor porpoises and harbor seals from construction of the Horns Rev 2 offshore wind farm. Analyzed acoustic data from five porpoise-detector stations spanning 1,891 data-days (2002–2005) and 51 ship-based visual surveys of approximately 400 km each. Modeled habitat quality using hydrodynamic simulations and identified critical porpoise habitat concentrated on the southwestern slopes of the site, estimating an 80 km hearing zone and a 20 km behavioral-response zone from pile-driving noise, with recommended construction mitigation measures including seal scarers and pingers.