When you think of an animal that purrs, grunts, croaks or hums, I’ll bet it’s not a fish. But, I’ll let you in on a secret: More than 150 species of fish on the East Coast of the U.S. are what scientists call “somniferous.” They make noise. Lots of it.Forget those dreamy underwater documentaries where all is peace and quiet. The ocean is like New York City at rush hour. There are thousands of species, and many have something to say. The tiny cusk eel sounds like a jackhammer. Damselfish purr. Long-horned sculpins hum like an iPhone set on “buzz.----