His research interests include maritime history, African-American history, environmental history, and Atlantic history. He enjoys exploring historical problems regarding peoples’ interaction with the sea. As a social historian he is especially interested in the relationship of experience and meaning. As an environmental historian he is intrigued with anthropogenic changes to the sea and the ways those changes have influenced human society and culture. He has written on African American seamen in the age of sail; the social and environmental history of the Piscataqua estuary that separates Maine and New Hampshire; shipping in the making of America; and most recently, the marine environmental history of the northwest Atlantic.