What does the realized niche refer to in ecological terms?

The realized niche refers to the specific set of conditions and resources that a species actually uses when faced with competition and other ecological interactions in its environment. This concept captures the actual habitat that a species occupies, taking into account the biotic (living) and abiotic (non-living) factors that limit its distribution and abundance.

In contrast to the fundamental niche, which represents the full potential range of conditions and resources a species could theoretically exploit in the absence of competition or predation, the realized niche reflects the realities of ecological interactions. These factors, such as competition for resources, predation, and environmental limitations, shape where and how a species lives in practice. Therefore, the focus on what a species actually occupies is key to understanding its survival and ecological role.

Other choices pertain to different ecological concepts, such as population dynamics and habitat capacity, which do not directly define the realized niche.