A perfect storm: The combined effects on population fluctuations of autocorrelated environmental noise, age structure, and density dependence

Christopher C. Wilmers, Eric Post, Alan Hastings

Research output: Contribution to journalArticlepeer-review

38 Scopus citations

Abstract

While it is widely appreciated that climate can affect the population dynamics of various species, a mechanistic understanding of how climate interacts with life-history traits to influence population fluctuations requires development. Here we build a general density-dependent age-structured model that accounts for differential responses in life-history traits to increasing population density. We show that as the temporal frequency of favorable environmental conditions increases, population fluctuations also increase provided that unfavorable environmental conditions still occur. As good years accumulate and the number of individuals in a population increases, successive life-history traits become vulnerable to density dependence once a return to unfavorable conditions prevails. The stronger this ratcheting of density dependence in life-history traits by autocorrelated climatic conditions, the larger the population fluctuations become. Highly fecund species, and those in which density dependence occurs in juvenile and adult vital rates at similar densities, are most sensitive to increases in the frequency of favorable conditions. Understanding the influence of global warming on temporal correlation in regional environmental conditions will be important in identifying those species liable to exhibit increased population fluctuations that could lead to their extinction.

Original languageEnglish (US)
Pages (from-to)673-683
Number of pages11
JournalAmerican Naturalist
Volume169
Issue number5
DOIs
StatePublished - May 2007

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics

Fingerprint Dive into the research topics of 'A perfect storm: The combined effects on population fluctuations of autocorrelated environmental noise, age structure, and density dependence'. Together they form a unique fingerprint.

Cite this