Bernt-Erik Saether and Steinar Engen. Norwegian University of Science and Technology
Predicting the risk of extinction requires estimates of the parameters determining the determinstic component of the population dynamics as well as the stochastic influences caused by demographic and environmental stochasticity. Here we present estimates of expected time to extinction for a large number of bird populations. As expected from theory, environmental stochasticity and specific population growth rate at small population sizes strongly influence the expected lifetime of a population. Furthermore, the population size for obtaining a given expected lifetime increases towards the 'fast' end of the slow-fast continuum of life history variation due to increased influence of environmental stochasticity of short-lived species.