Individual variation in life history characteristics can influence extinction risk

Authored by HI Jager

Date Published: 2001

DOI: 10.1016/s0304-3800(01)00362-3

Sponsors: United States Department of Energy (DOE) Electric Power Research Institute (EPRI) Oak Ridge National Laboratory (ORNL)

Platforms: No platforms listed

Model Documentation: Other Narrative Flow charts Mathematical description

Model Code URLs: Model code not found

Abstract

The white sturgeon (Acipenser transmontanus) shows great individual variation in the age at maturation. This study examines the consequences of model assumptions about individual variation in the age at maturation on predicted population viability. I considered: (1) the effects of variation in age at maturation alone; (2) the effects of heritability; and (3) the influence of a stable and an altered selective regime. Two selective regimes represented conditions before and after the impoundment of a river, blocking access of anadromous white sturgeon populations to the ocean. In contrast to previous simulation studies, I found that increased individual variation in the age at maturity did not necessarily lead to a higher likelihood of persistence. Individual variation increased the simulated likelihood of persistence when the variation was heritable and the selective regime had changed such that the mean age at maturity was no longer optimal. (C) 2001 Elsevier Science B.V. All rights reserved.
Tags
Evolution Dynamics Population persistence Model Traits Demographic stochasticity White sturgeon Fish populations Sturgeon acipenser-transmontanus Selection differentials