The Princeton Guide to Ecology

Separately and in combination, the terms habitat and selection mean different things to different audiences. This chapter focuses on habitat selection behavior at the level of individuals and considers how the processes that affect the choices made by organisms at different spatial scales affect the distributions at the population level. Because we initially focus on habitat selection at the level of individuals, habitat can be defined as a location in which a particular organism is able to conduct activities that contribute to survival and/or reproduction. That is, habitat is organismspecific rather than being determined by features that may be obvious to humans (e.g., vegetation type). Selection can be defined as a behavioral process by which an organism chooses a particular habitat in which to conduct specific activities. Hence, habitat selection implies that individual organisms have a choice of different types of habitat available to them and that they actively move into, remain in, and/or return to certain areas rather than others.

conspecific attraction. Attraction of individuals to conspecifics during the process of habitat selection

habitat selection. The process by which individuals choose areas in which they will conduct specific activities

heterospecific attraction. Attraction of individuals to other potentially competing species during the process of habitat selection

indirect cues. Stimuli that are produced by factors that are correlated with other factors with direct effects on intrinsic habitat quality

intrinsic habitat quality. The expected fitness of an individual when it uses or lives in a given habitat, after controlling for any effects of conspecifics on fitness

microhabitat. An area used for a specific type of activity (e.g., foraging, oviposition, nesting)

natal habitat preference induction. Exposure to cues in an individual’s natal habitat increases the attractiveness of those cues during habitat selection

Habitats and habitat selection can occur at several different spatial and temporal scales. At larger scales, habitat refers to areas that are required for the long-term survival and reproduction of the members of a given population. In this case, habitat includes all of the areas required by all of the life stages of the members of that population, including areas that allow dispersers to travel among different patches of suitable habitat. For instance, from the perspective of a migratory bird, habitat includes breeding habitat, wintering habitat, and migratory stopovers that connect these venues. Habitat selection at large spatial and temporal scales occurs when individuals choose localities or regions that might be capable of supporting them, their offspring, and their descendents for an extended period of time.

At intermediate spatial and temporal scales, habitat refers to an area capable of supporting an individual for a biologically significant, finite period of its lifetime. Examples of habitat at this spatial scale include the selection of a feeding territory by a juvenile salmonid or an area suitable for feeding and oviposition by a female butterfly. Habitat selection at this scale is particularly important for sessile organisms such as barnacles because in this case a decision made early in life affects an individual’s fitness for the rest of its life. In contrast, mobile organisms may select new habitats several times over the course of their lives as a result of changes in resource requirements, experience, or

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