Avian Issues for Offshore Wind Development

In the United States, the fastest growing source of electricity is wind energy, and offshore environment-generated energy potential is enormous. The authors briefly review offshore wind energy effects on birds - the focus of environmental concerns - in the context of preconstruction risk and postconstruction impact assessment methodology. Prior to construction, prospective developers will be required to conduct some form of avian risk assessment due to such federal statutes and legislation, including the Migratory Bird Treaty, the Endangered Species Act, the Federal Energy Act of 2005, and the National Environmental Policy Act. Birds face three primary threats from offshore wind farms: displacement-based habitat loss, fatalities due to turbine blade collisions, and flight avoidance-based barrier effects. At coastal and land-based wind farms, all threats have been demonstrated, and, in the offshore environment, for limited number of species in Europe, shifts in habitat use and flight avoidance have been demonstrated. Under current development levels, there may be a trivial additive effect of these impacts to bird populations, but with the projected increase in offshore installations, such effects could become ecologically significant. Additional research, especially on winter foraging habitat and population delineation importance understanding, particularly for waterfowl, is required for ecological significance interpretation of these effects. The authors suggest, as is currently underway in some states, public-private partnerships and public funding of these efforts, since such reconstruction and research studies will be expensive.