I am a deep water fish, rarely seen with the same name as a boat instrument

I’m a very relaxed mollusk, that is until I get turned into chowder.

I'm Moby Dic's worst enemy, not Ishmael, but sinister indeed. From the bow, I enter thee, piercing deep, you'll come to me.

Behold the humble hut of yore, where beasts dost bide from tempest's roar. A wooden womb for woolly kin, beneath its roof, calm doth begin.

Silent sentinels standing tall, wearing crowns of green. They sway with the whispers of the wind and shelter the world beneath their leafy arms.