Tautog is a popular fish for recreational fishers - not really a sporty fish but a dining fish. It's no surprise that they are tasty because they live on molluscs and crustaceans. These guys (they are a Wrasse) live mainly from Cape Cod to Chesapeake Bay.
There's a limited keeping season for them: April, and then mid-Oct to mid November.
They are bottom-feeders, partial to rocky bottoms, underwater structure. Green crabs and clams are the best bait.
From a piece on Blackfish - Throw the big ones back:
Tautog (Tautoga onitis), also known as blackfish, have a lifestyle that promotes a long life: they eat crabs and shellfish, sleep all winter, and in the summer they rest every night and have sex every day.
Not a bad life. In youth, I would catch a few off the wreck outside Wellfleet Harbor. The one in the photo is huge, probably should be tossed back to breed but you can tell from that gal's face that she wants to eat it.