6 Population Ecology and Dynamics

Like other animals, grouse and quail exist as natural populations dependent upon particular habitats and vary in population density between the absolute minimum populations that have permitted past survival to fairly dense populations that may approach or even temporarily exceed the carrying capacity of the habitat. Each species may also have an upper limit on the density of the population, or a saturation point, which is independent of the carrying capacity of the habitat but is determined by social adaptations. Within the population as a whole, individual birds or coveys may have home ranges, geographical areas to which their movements are limited and within which they spend their entire lives. Part of the home range may be defended by individuals so that conspecifics of the same sex are excluded for part or all of the year; such areas of localized social dominance and conspecific exclusion are called territories. Among species lacking discrete territories and in which the social unit is the covey or flock rather than the pair or family, dominance hierarchies, or peck orders, may serve to integrate activities in the flock. These behavioral adaptations and habitat relationships play important roles in population ecology, and will be considered in detail in the individual species accounts. However, a preliminary survey may help to provide generalizations that will be useful to keep in mind when considering individual species