A starfish is classified as a secondary consumer in the marine food web. Secondary consumers are organisms that primarily eat primary consumers, which are usually herbivores or primary producers.
Starfish primarily feed on mollusks such as clams, oysters, and snails. They use their strong arms to pry open the shells of these animals, and then they protrude their stomachs out to digest the food outside their bodies before absorbing the nutrients. This unique feeding method categorizes them as carnivores, making them secondary consumers because they rely on other organisms for food, rather than producing it themselves.