Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

Environmental Variation and the Persistence of Small Populations

Environmental Variation and the Persistence of Small Populations Understanding the factors that determine the continued survival of small populations is a central problem in conservation biology. The Acorn Woodpecker (Melanerpes formicivorus) naturally occurs in small, isolated populations throughout much of the American Southwest. In spite of this distributional pattern, the species is neither rare nor endangered. Thus it appears to have successfully "solved" the problems to the problems of habitat fragmentation. We used data from a 10—yr field study and simulation models to examine the effects of environmental stochasticity on population survival times. All simulated woodpecker populations went extinct within 49 yr, and the median survival time was only 16 yr. However, when immigration was allowed, persistence times greatly increased; with an immigrant rate of only five individuals per year, most populations lasted >1000 yr. The results of this and other analyses suggest that this population persists only because it is part of a larger "metapopulation," and because it is regularly rescued from extinction by immigration from other, independently varying, populations. This finding has important implications for the development of management strategies designed to preserve small populations that are faced with fragmented distributional patterns and high levels of environmental variation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Ecological Applications Wiley

Environmental Variation and the Persistence of Small Populations

Stacey, Peter B.; Taper, Mark
Ecological Applications , Volume 2 (1) – Feb 1, 1992
Download PDF
12 pages

Loading next page...
 
/lp/wiley/environmental-variation-and-the-persistence-of-small-populations-Go0R8KKACU

References (48)

Publisher
Wiley
Copyright
© Society for Community Research and Action
ISSN
1051-0761
eISSN
1939-5582
DOI
10.2307/1941886
Publisher site
See Article on Publisher Site

Abstract

Understanding the factors that determine the continued survival of small populations is a central problem in conservation biology. The Acorn Woodpecker (Melanerpes formicivorus) naturally occurs in small, isolated populations throughout much of the American Southwest. In spite of this distributional pattern, the species is neither rare nor endangered. Thus it appears to have successfully "solved" the problems to the problems of habitat fragmentation. We used data from a 10—yr field study and simulation models to examine the effects of environmental stochasticity on population survival times. All simulated woodpecker populations went extinct within 49 yr, and the median survival time was only 16 yr. However, when immigration was allowed, persistence times greatly increased; with an immigrant rate of only five individuals per year, most populations lasted >1000 yr. The results of this and other analyses suggest that this population persists only because it is part of a larger "metapopulation," and because it is regularly rescued from extinction by immigration from other, independently varying, populations. This finding has important implications for the development of management strategies designed to preserve small populations that are faced with fragmented distributional patterns and high levels of environmental variation.

Journal

Ecological Applications – Wiley

Published: Feb 1, 1992

There are no references for this article.