A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources. Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor. Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor. There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species. Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support.
Teach your students about limiting factors with this curated collection of resources.