Minimum Viable Population - Estimating The MVP

Estimating The MVP

Minimum Viable Population is usually estimated as the population size necessary to ensure between 90 and 95 percent probability of survival between 100 to 1,000 years into the future. The MVP can be estimated using computer simulations for population viability analyses (PVA). PVA models populations using demographic and environmental information to project future population dynamics. The probability assigned to a PVA is arrived at after repeating the environmental simulation thousands of times.

For example, a simulation of a population of fifty giant pandas in which the simulated population goes completely extinct thirty out of one hundred stochastic simulations when projected one hundred years into the future is not viable. Causes of extinction in the simulation may include inbreeding depression, natural disaster, or climate change. Extinction occurring thirty out of one hundred runs would give a survival probability of seventy percent. In the same simulation with a starting population of sixty pandas, the panda population may only go extinct on four of the hundred runs for a survival probability of 96 percent. In this case the minimum viable population that satisfies the 90 to 95 percent probability for survival is between 50 and 60 pandas. (Numbers and species were invented for the purpose of this example).