BIOL 3130 Lecture Notes - Lecture 18: Loggerhead Sea Turtle, Allele, Population Viability Analysis
Document Summary
Population viability analyses (pvas): synthesis of knowledge about a species, its environment, and human actions in a model of population dynamics. Population growth can be influenced by several factors that can influence predictions of future population size. Environmental stochasticity (random fluctuations: environmental catastrophes and goldmines (large perturbations, demographic stochasticity (chance variation in vital rates [e. g. allele effects]) One of the key results of population models is that variation in population growth reduces survival. Even if the average growth rate (arithmetic mean) is the same, increase variation results in smaller (geometric mean) growth rate: adding variation to population growth usually reduces population growth. Population viability: defined as the probability that it will not go extinct during a fixed time span, given the current population size. Not very reliable: don(cid:495)t have great data to make preservation solutions tend not to know how many individuals of a species-which is needed/helpful. Demograpgy: what can be measured total population size (nt)