California’s oceanic waters provide habitat for numerous migratory, resident, and breeding species of seabirds and marine mammals. Recent technological advances have made offshore wind energy infrastructure development a possibility for the deep waters off the U.S. West Coast. Multiple wind energy projects have been proposed for the region between the central California Coast and the United States-Mexico border and are under consideration by State and Federal regulators.
Given existing stresses to marine species, birds and mammals are vulnerable to the added effects of wind energy development. In a recent report, the USGS Western Ecological Research Center (WERC) Seabird Team assessed the vulnerability of seabirds to wind energy infrastructure. Now, with direction and support from the Bureau of Ocean Energy Management (BOEM), the Seabird Team has begun a series of aerial bird and mammal surveys that will provide more current information about animal distributions and abundance at sea to augment the initial vulnerability assessment. The results will inform the offshore wind development permit and planning process and help managers identify potential wildlife interactions with offshore wind energy infrastructure.
In the first part of the project, USGS WERC scientists are conducting aerial surveys from a small airplane from Point Piedras Blancas on the central California Coast to the United States-Mexico border. Survey aircraft are outfitted with sophisticated digital cameras linked to computers to capture thousands of high-resolution digital photographs. Aerial surveys will take place over two years, covering the full study area in summer, fall, and winter, with additional surveys during migratory periods.
The aerial surveys will produce hundreds of thousands of images. Some of the images will contain birds and mammals, but many will only feature the surface of the ocean. Picking out the valuable species data from the vast number of images would be a herculean task for a human and doing so for sets of images dominated by animal-free photos is currently a challenge even for computers. Using rapidly developing machine learning techniques, the USGS WERC team is designing new methods to automate the detection and counts of seabirds and marine mammals from imagery. Use of artificial intelligence to extract quantitative information from images will allow researchers to share contemporary data about species composition, distribution, abundance, habitat associations, and seasonal variation. Maps of these data can be used to inform the planning process for offshore wind development.
Looking through the belly port of a small airplane before an aerial photographic survey starts, Fall 2018. (Credit: Laura White. Public domain.)