title: Sensitivity analysis of effective population size to demographic parameters in house sparrow populations.
abstract: The ratio between the effective and the census population size, Ne/N, is an important measure of the long-term viability and sustainability of a population. Understanding which demographic processes that affect Ne/N most will improve our understanding of how genetic drift and the probability of fixation of alleles is affected by demography. This knowledge may also be of vital importance in management of endangered populations and species. Here, we use data from 13 natural populations of house sparrow (Passer domesticus) in Norway to calculate the demographic parameters that determine Ne/N. Using the global variance-based Sobol' method for the sensitivity analyses, we found that Ne/N was most sensitive to demographic variance, especially among older individuals. Furthermore, the individual reproductive values (that determine the demographic variance) were most sensitive to variation in fecundity. Our results draw attention to the applicability of sensitivity analyses in population management and conservation. For population management aiming to reduce the loss of genetic variation, a sensitivity analysis may indicate the demographic parameters towards which resources should be focused. The result of such an analysis may depend on the life history and mating system of the population or species under consideration, because the vital rates and sex-age classes that Ne/N is most sensitive to may change accordingly.
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Marlene Waege
authors.initials: MW
authors.lastname: Stubberud
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Ane Marlene
authors.initials: AM
authors.lastname: Myhre
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Håkon
authors.initials: H
authors.lastname: Holand
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kvalnes
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Thor Harald
authors.initials: TH
authors.lastname: Ringsby
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Bernt-Erik
authors.initials: BE
authors.lastname: Saether
authors.affiliation: Department of Biology, Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
authors.forename: Henrik
authors.initials: H
authors.lastname: Jensen
mesh_terms: D000818:Animals; D003247:Conservation of Natural Resources; D003710:Demography; D005298:Fertility; D040961:Genetic Drift; D014644:Genetic Variation; D009664:Norway; D011156:Population Density; D046370:Sparrows / Q000235:genetics*
keywords: effective population size; population management; population size; sensitivity analysis; two-sex demographic model