Who but little seagulls and little crucian carp can clean the oceans?

1 Scavenger, a species of fish, is native to South America. It owes its name to the fact that it feeds on various underwater waste and can swallow sick fish.

2 Sharks may eat these infected fish (like scavengers) to keep the ocean “healthy”. Because sharks are carnivorous, they feed and clean the ocean by eating meat, hence the term ". “unpaid ocean cleaner” is relatively recognized.

3 Manatees eat seaweed and other algae every day and sometimes pave the way for ships, which is why they are called cleaners of oceans.