Findings from two four-year offshore surveys provide new “baseline biological” information about whales, sea turtles and birds that live in federally designated Wind Energy Areas (WEAs) off Massachusetts and Rhode Island.
From 2011 to 2015 research teams from the National Oceanic and Atmospheric Administration and independent academic institutions studied the occurrence and distribution of wildlife across the WEAs, where wind energy developers could build large turbine arrays on federal leases. The studies were sponsored by the federal Bureau of Ocean Energy Management and Massachusetts Clean Energy Center.
BOEM released the results during this week’s offshore wind energy conference, hosted in Rhode Island by the American Wind Energy Association. The agency struck an optimistic note in its announcement, saying “the wildlife surveys found that the Massachusetts and Rhode Island WEAs avoid the high concentrations of protected species of whales, turtles and seabirds in these areas.”
But the researchers themselves had some cautious recommendations. Foremost, they wrote that the seasonal and spatial movements they observed with whales and sea turtles indicate that those times and areas will need special management as part of permitting for turbine construction projects.
“Using this study as a baseline, a long-term study on potential displacement and disturbance should be designed and implemented. It will require comparable, but targeted surveys both during construction and after full operations have commenced to answer the questions about wind farm effects on large whales and sea turtles,” the scientists reported.
One species of particular concern is the northern right whale, one of the most endangered marine mammal species in the world. The survey’s combined use of aerial spotting and acoustic listening for whale sounds showed right whales are present in parts of the study area in spring and summer.
“This study suggests a substantial number of them are regular visitors, and that the habitat may be more important than recognized,” the researchers noted. More focused oceanographic studies are needed in the area to learn more about when and where endangered whales are in those waters, they wrote.
“Most importantly for future wind farm development, it will be important to separate two hypotheses. One, do wind farms alter the acoustic or physical characteristics in ways that cause displacement of whales to other areas?” they suggested. A second possibility is that changes in the whales’ distribution and behavior happen because their food supply changes: “Distinguishing between these two hypotheses will be important in the context of managing future development.”
Time and area closures during construction could be one way of reducing interactions with marine mammals. Some critics of offshore wind development including commercial fishermen worry construction activity and noise will drive away sea life.
Advocates will point to study results that found larger seasonal gatherings of species occurred closer to the northeast and southern edges of the WEAs.
"BOEM remains deeply committed to ensuring that renewable energy development on the Outer Continental Shelf is done in a safe and environmentally responsible manner,” BOEM Director Abigail Ross Hopper said in announcing the findings. “The survey results confirm that responsible commercial wind development activities in these WEAs will not adversely affect protected species populations."