Vineyard Wind is offering to pay Rhode Island fishermen $6.2 million in compensation for lost access to fishing grounds as part of a mitigation plan for its proposed offshore wind farm that also includes the creation of a $23-million fund to research new gear and technology to support safe fishing in and around wind turbines. As expected, the offer to the state’s fishermen who catch squid, lobster and Jonah crab in the project waters south of Martha’s Vineyard falls short of what they wanted.One benchmark for the potential drop in revenues they would suffer from losing access to the waters where Vineyard Wind wants to erect 84 giant turbines comes from an analysis by the Rhode Island Department of Environmental Management, which put the number at between $30.5 million and $35.6 million over the 30-year life of the wind farm.