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Published on: May 1, 2018
The role of density-dependent dispersal in source-sink dynamics
1Department of Ecology and Evolution, The University of Chicago, 1101 East 57th Street, Chicago IL 60637, USA. amarasek@midway.uchicago.edu
Journal of Theoretical Biology
|December 4, 2003
Summary
Source-sink persistence hinges on density-dependent dispersal and its costs. Accelerating emigration rates minimize extinction risk, while decelerating rates maximize it, highlighting the crucial role of dispersal modes.
Area of Science:
- Ecology
- Population Dynamics
- Conservation Biology
Background:
- Source-sink dynamics are crucial for metapopulation persistence.
- The impact of density-dependent dispersal and its costs on source-sink stability is understudied.
- Emigration can reduce source population growth rates, increasing extinction risk.
Purpose of the Study:
- To investigate the influence of density-dependent dispersal on source-sink persistence.
- To analyze the costs of dispersal to source populations.
- To determine how different modes of density-dependent dispersal affect source-sink stability.
Main Methods:
- Theoretical modeling of source-sink dynamics.
- Analysis of per capita growth rates in source and sink populations.
- Simulation of population dynamics under varying emigration rates.
Main Results:
- Source-sink persistence critically depends on the interplay between dispersal rate and density-dependence.
- Accelerating emigration rates (increasing with abundance) minimize dispersal costs and extinction risk.
- Decelerating emigration rates (increasing with abundance) maximize dispersal costs and extinction risk.
- Density-independent dispersal has an intermediate effect on extinction risk.
Conclusions:
- The mode of density-dependent dispersal is a critical factor in source-sink stability.
- Dispersal-induced temporal density-dependence can benefit sinks at low abundances but harm sources at high abundances.
- These findings aid in evaluating the costs and benefits of conserving sink habitats.
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