Consumers are organisms that consume the food produced, either directly or indirectly.
Based on their manner of feeding, consumers can be classed as primary, secondary, or tertiary. 

• Primary consumers include all herbivores and some parasites - Rabbits, for example, consume grass.
• Secondary consumers include many tiny carnivores and parasites - A snake that eats rabbits is an example. 
• Tertiary consumers include larger carnivores and omnivores - An owl, for example, eats snakes.