The federal Bureau of Ocean Energy Management has cut approximately 140 square miles from a wide swath of ocean south of the Vineyard potentially open to wind farm developers.

On Wednesday the federal agency announced that it had finished defining the boundary of federal waters that would be considered for possible wind farm development, known as the wind energy area. BOEM had previously cut the area, which starts 12 miles south of the Vineyard, from 3,000 square miles to 1,300 square miles. On Wednesday the agency announced that the latest reductions were made to reflect concerns about foraging sea ducks as well as commercial fishing interests in an area known as Cox’s Ledge between Martha’s Vineyard and Block Island.

According to a press release from BOEM, the agency will now conduct an environmental assessment on the area that will consider, “among other things, potential impacts on endangered North Atlantic right whales and effects on viewshed.”