History
In the 1970s, Yellowstone National Park was the centre of a heated debate over different proposals to manage the Park’s problem grizzly bears (Ursus arctos). In 1978, Mark Shaffer proposed a model for the grizzlies that incorporated random variability, and calculated extinction probabilities and minimum viable population size. The first PVA is credited to Shaffer.
PVA gained popularity in the United States as federal agencies and ecologists required methods to evaluate the risk of extinction and possible outcomes of management decisions, particularly in accordance with the Endangered Species Act of 1966, and the National Forest Management Act of 1976.
In 1986, Gilpin and Soulé broadened the PVA definition to include the interactive forces that affect the viability of a population, including genetics. The use of PVA increased dramatically in the late 1980s and early 1990s following advances in personal computers and software packages.
Read more about this topic: Population Viability Analysis
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—Henry David Thoreau (1817–1862)
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—Evelyn Waugh (1903–1966)