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Predicting the Effectiveness of Population Replacement Strategy Using Mathematical Modeling
Published on: July 4, 2007
A stochastic model for annual reproductive success
Bruce E Kendall1, Marion E Wittmann
1Donald Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA. kendall@bren.ucsb.edu
The American Naturalist
|February 19, 2010
Summary
We developed a new stochastic model for annual reproductive success (ARS) to better understand population dynamics. This model accounts for key survival events and reveals that ARS distributions are often multimodal, impacting extinction risk in small populations.
Area of Science:
- Ecology
- Population Biology
- Evolutionary Biology
Background:
- Demographic stochasticity significantly impacts small populations and rare lineages.
- Existing models inadequately capture the complexity of annual reproductive success (ARS).
Purpose of the Study:
- To introduce a novel stochastic model framework for ARS.
- To analyze the properties and implications of this ARS model.
Main Methods:
- Modeled ARS as a sequence of stochastic events: nesting, offspring production, predation, and survival.
- Utilized generalized Poisson distribution for offspring number variability, validated with 53 vertebrate species data.
- Incorporated multiple nesting attempts and Bernoulli/binomial processes.
Main Results:
- Demonstrated that among-individual variability in offspring number often follows a generalized Poisson distribution.
- Calculated demographic variance from underlying biological processes.
- Revealed that ARS distributions are frequently multimodal and skewed.
Conclusions:
- The new model provides a flexible framework for studying demographic stochasticity in ARS.
- Skewed and multimodal ARS distributions have significant implications for extinction risk and evolutionary dynamics in small populations.
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