The blue whale eats about 4 tons of krill daily to support its 200-ton mass. When comparing food intake to body mass, however, hummingbirds are much bigger eaters. These tiny birds consume up to eight times their weight in nectar, pollen and insects daily.
The amount of food an animal needs depends on its size, its activity level and whether it is warm-blooded or cold-blooded. While large animals need more food than small ones, their metabolism increases at a slower rate than their mass does. This means that large animals usually need less food per unit of body weight than smaller ones. High levels of activity drive up the need for food, and warm-blooded animals need about eight times the energy intake of cold-blooded animals of similar mass to maintain body temperature.