Flexi Says: The trophic level of an animal depends on what organisms the animal eats. Herbivores such as mice and deer are primary consumers that eat only producers (plants), and are on the second trophic level. Carnivores that eat herbivores are secondary consumers, and are on the third trophic level. Carnivores that eat other carnivores are tertiary or quaternary consumers, and are on the fourth or fifth trophic level.
