Population Viability Analysis

Initial population (N₀)

Growth rate (r)

0.10

Demographic variance (σd²)

0.30

Environmental variance (σe²)

0.10

Carrying capacity (K)

200

Years

100

Results

Extinction prob:—

Median final N:—

MVP (P_ext<5%):—

Population Viability Analysis (PVA) uses stochastic models to estimate extinction probability for a given population size. Two sources of randomness operate: demographic stochasticity (random births/deaths at the individual level, dominant at small N) and environmental stochasticity (year-to-year variation in habitat quality, affecting all individuals simultaneously). The minimum viable population (MVP) is conventionally defined as the smallest N yielding <5% extinction risk over 100 years. The MVP typically ranges from 50–1000 individuals depending on species life history.