Answer:
I am a busy worker who is a water mammal.
I can be swallowed, but I can also swallow you. What am I?
Deep, deep, do they go. Spreading out as they go. Never needing any air. They are sometimes as fine as hair.
I roam through the lands hoping to rescue my love. I search high and low and will stomp on you if you get in my way!
I am a cold man without a soul. If there is warmth in me, it slowly will kill me. What am I?
you hold my tail while I fish for you