Population viability

Population viability

The ability of a population to persist and to avoid extinction. The viability of a population will increase or decrease in response to changes in the rates of birth, death, and growth of individuals. In natural populations, these rates are not stable, but undergo fluctuations due to external forces such as hurricanes and introduced species, and internal forces such as competition and genetic composition. Such factors can drive populations to extinction if they are severe or if several detrimental events occur before the population can recover. See Ecology, Population ecology

One of the most important uses of population viability models comes from modern conservation biology, which uses these models to determine whether a population is in danger of extinction. This is called population viability analysis (PVA) and consists of demographic and genetic models that are used to make decisions on how to manage populations of threatened or endangered species. The National Research Council has called population viability analysis “the cornerstone, the obligatory tool by which recovery objectives and criteria [for endangered species] are identified.” See Ecological modeling