"Cape Wind really helped focus attention on what we didn't know and what we needed to know for offshore wind in order to estimate risk," said Taber Allison, director of research at the American Wind and Wildlife Institute. (The institute is a partnership of conservation organizations and wind industry companies.) Allison is also an adviser to BOEM's outer continental shelf scientific committee and formerly a vice president at Mass Audubon, which endorsed Cape Wind after three years of survey and tracking of terns and long-tailed ducks in Nantucket Sound.
"The challenge for BOEM is they're dealing with an area that's far larger and for which we have very little data," he said. "We don't have armies of birders offshore."
European experience with wind turbines has revealed little risk of collision with seabirds but possibly some habitat displacement. To be safe, BOEM is trying to stay out of the birds' way. The 1,161-square-mile leasing area near Massachusetts, announced in May, was shrunk from more than 3,000 square miles in the past year in deference to long-tailed ducks, which forage in the area, as well as to commercial fishing interests.
"They appear to be very responsive to the interests of the fishermen," said Eric Hansen, a third-generation scalloper out of New Bedford, Mass. However, he added, "there's always the question about whether they made the area so large to make it look good when they knew they were going cut it down anyways, but it on the surface it's been very good."
Underwater, BOEM has been evaluating more subtle factors. Studies funded by the agency are exploring the effect on sharks and rays of electromagnetic fields generated by undersea cables that will connect the turbines. It is also evaluating the effects of pile-driving and turbine noise on whales, sea turtles and fisheries.