Foxes do eat rabbits. In the food chain, rabbits are primary consumers that are herbivores, and foxes are secondary consumers. Secondary consumers can be either omnivores or carnivores. The fox is an omnivore, so while the rabbit eats plants, the fox eats many types of food.
On a food chain, a rabbit and a red fox are also examples of a predator-prey relationship. A food chain consists of trophic levels that include producers, primary consumers, secondary consumers, tertiary consumers and decomposers. A food chain can demonstrate the interconnections of animals in an ecosystem. For example, rabbits, as primary consumers, eat grass, which is a producer. Red foxes, as secondary consumers, prey on rabbits, and a coyote, as a tertiary consumer, preys on fox pups.
The food chain also shows all the foods that an animal can eat. Besides rabbits, foxes can eat berries, fruits, birds, insects, rodents and many other small mammals.