Depending on the species, some sea worms eat crabs, other worms, snails, crustaceans and fish, while some are parasites that eat crab eggs or anything that can be scavenged from a host. The ribbon worm lives in the sandy seafloor and covers its prey with a toxic slime, paralyzing it.
Sea worms are a large and varied species with the ribbon worm having over 1,000 variations. Sea worms range in size from less than 1/2 inch long, to the largest species, the bootlace worm, which measures 98 feet. Sea worms' muscles contract and expand, allowing them to eat other worms, crustaceans, clams and fish that are twice their size.