You do not have to go into fiction, plants eat light!
No. However, cricket like creatures may in science fiction.
the Japanese
After just a few hundred metres there is very little light. Most deep sea creatures have very large eyes that can detect any light that is available. Even though there is virtually no light coming from the surface lots of deep sea creatures produce light through a process called bioluminescence. It is useful to be able to see this light as if you eat the light, you will be eating the creature that it is attached to. Unfortunately some creatures use these lights to draw in their own dinner!
Basically, whatever habits the story teller gives them; chupacabra are creatures of fiction and myth. They will eat some of the flesh of any animal, or human. Although their main love is blood.
Any type of fish that swims by
they will eat any small creatures. This includes fish, mice, frogs and water snakes.
turtles do sometimes for thier diet
Pescatarians can eat any type of seafood. Any other type of vegetarian (strict, ovo, lacto) cannot eat any type of seafood.
You are confusing fact with fiction. Vampires are entirely fictional creatures. What they may or may not eat or drink is controlled by the author of the story.
Any sea creature, from the blue whale to the smallest krill, will be eaten by other creatures when they die.
Smaller ocean creatures.
the process in which larger creatures eat smaller creatures or plants