The Effect of Travel Loss on Evolutionarily Stable Distributions of Populations in Space

• Published in: The American naturalist 2011-07, Vol.178 (1), p.15-29
• Main Authors: DeAngelis, Donald L., Wolkowicz, Gail S. K., Lou, Yuan, Jiang, Yuexin, Novak, Mark, Svanbäck, Richard, Araújo, Márcio S., Jo, YoungSeung, Cleary, Erin A.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Aquatic Organisms; Biological and medical sciences; Biological Evolution; Biota; Conservation of Natural Resources; Cost efficiency; Ecological competition; Emigration; evolutionarily stable strategy; Food Chain; Food chains; foraging strategy with movement costs; Fresh water ecosystems; Fundamental and applied biological sciences. Psychology; General aspects; Growth rate; Habitats; ideal free distribution; metapopulation; Modeling; Models, Biological; Mortality; Movement; NATURAL SCIENCES; NATURVETENSKAP; Optimal strategies; Population size; Predators; stream drift; Synecology; Travel; Travel expenses
• ISSN: 0003-0147; 1537-5323; 1537-5323
• DOI: 10.1086/660280

A key assumption of the ideal free distribution (IFD) is that there are no costs in moving between habitat patches. However, because many populations exhibit more or less continuous population movement between patches and traveling cost is a frequent factor, it is important to determine the effects of costs on expected population movement patterns and spatial distributions. We consider a food chain (tritrophic or bitrophic) in which one species moves between patches, with energy cost or mortality risk in movement. In the two-patch case, assuming forced movement in one direction, an evolutionarily stable strategy requires bidirectional movement, even if costs during movement are high. In theN-patch case, assuming that at least one patch is linked bidirectionally to all other patches, optimal movement rates can lead to source-sink dynamics where patches with negative growth rates are maintained by other patches with positive growth rates. As well, dispersal between patches is not balanced (even in the two-patch case), leading to a deviation from the IFD. Our results indicate that cost-associated forced movement can have important consequences for spatial metapopulation dynamics. Relevance to marine reserve design and the study of stream communities subject to drift is discussed.