Are Keystone species always predators?

Sea otters are important predators of sea urchins, an animal that eats giant brown kelp in continental shelf z?

• Sea otters are important predators of sea urchins, an animal that eats giant brown kelp in continental shelf zones where they form huge kelp beds. It was observed that the removal of sea otters from the west coast led to an increase in the sea urchin population. These sea urchins fed on the large kelp fronds, destroying the kelp beds that serve as an important source of food and protection for spawning fish. What role does the sea otter play in this case? A.) Dominant species B.) Invasive species C.) Keystone species

• Answer:

  C.) Keystone species