A niche is the role an organism fills within its environment. What and where an animal eats are considered part of its niche. For instance, some birds, such as woodpeckers, eat insects in trees. This limits the bug population and keeps bugs from overtaking the environment.
The job, or niche, of some small animals, including chipmunks and squirrels, is to spread food. Seeds, nuts and berries that are stored but not eaten grow into new plants. Also, some seeds are moved to different areas through animals' feces. The resulting plants are eaten by other herbivores. The niche of predators, such as lions, is to eat smaller animals, which keeps those populations from getting out of control.