A consumer is pretty much an animal that consumes or eats food, this animal doesnt make its own food like producers such as plants do. Some examples of consumers are: bears, foxes, rabbits, and caribou.
Consumers are plants/animals that cannot make their own food. Conversely, producers are organisms that can (usually plants, in the process of photosynthesis. Since a black rhino cannot make its own food, it is considered a consumer.