1. The space occupied by a biological species, which includes both the physical space as well as the functional role of the species.
2. The specific microhabitat in which a particular population lives and the way that population exploits that microhabitat.

Ecological niche refers to the characteristics of an environment that provides all the essential food and protection for the continued survival of a particular species of flora or fauna.

In addition to food and shelter, there is no long-term threat to existence in that place from potential predators, parasites, and competitors. The concept of the ecological niche goes a long way beyond the idea of the species habitat.