But sound produced by human activity can get in the way. In the waters off Massachusetts, oceanic scientists have observed that many whales no longer seem to register the sounds of ships, said Richard Merrick, the chief scientist for the oceanic administration’s fisheries service. They do not necessarily associate the sounds of ships with danger, he said, so they do not always move out of the way.

Elsewhere, other species of whales, he said, “just shut up” when ships pass by, in part because many species communicate using sounds in the same range of frequency as the noise produced by ship engines.

And some studies have demonstrated that cod and haddock populations in the Atlantic, both of which are considered or are becoming overfished, can hear and also avoid low-frequency sounds, though it is not clear what the effects might be on their behavior, said Jason Gedamke, an acoustics expert with the oceanic administration and a lead author of the road map. Cod, in particular, also make lots of noise when they spawn, but the implications of human sound on that behavior is not fully known, either, Dr. Gedamke said.