Although blue whales are carnivores and are the biggest creature on Earth, they only eat very small creatures. They feed almost exclusively on a small shrimp like creature called krill. "Blue whales must eat two to four tons of krill a day during the feeding season to survive the rest of the year." They also eat a small amount of zooplankton. This feast takes place within a hundred meters from the surface. Their feeding season is during the summer, but during the other 8 months of the year the live on their stored fat.
This is a picture of a krill. You may now realize why these whales eat so much of it.
