Publication Date:
2022-05-25
Description:
Author Posting. © University of Chicago Press, 2015. This article is posted here by permission of University of Chicago Press for personal use, not for redistribution. The definitive version was published in American Naturalist 186 (2015): 362-375, doi:10.1086/682276.
Description:
Some of the most fundamental quantities in population ecology describe the growth and spread of populations. Population dynamics are often characterized by the annual rate of increase, λ, or the generational rate of increase, R0. Analyses involving R0 have deepened our understanding of disease dynamics and life-history complexities beyond that afforded by analysis of annual growth alone. While range expansion is quantified by the annual spreading speed, a spatial analog of λ, an R0-like expression for the rate of spread is missing. Using integrodifference models, we derive the appropriate generational spreading speed for populations with complex (stage-structured) life histories. The resulting measure, relevant to locations near the expanding edge of a (re)colonizing population, incorporates both local population growth and explicit spatial dispersal rather than solely growth across a population, as is the case for R0. The calculations for generational spreading speed are often simpler than those for annual spreading speed, and analytic or partial analytic solutions can yield insight into the processes that facilitate or slow a population’s spatial spread. We analyze the spatial dynamics of green crabs, sea otters, and teasel as examples to demonstrate the flexibility of our methods and the intuitive insights that they afford.
Description:
Support for this work was provided,
in part, by a postdoctoral fellowship (A.W.B.), Discovery
Grants (M.K., M.A.L.), and an Accelerator Grant
(M.A.L.) from the Natural Sciences and Engineering Research
Council of Canada. The material is based on work
supported by the US National Science Foundation under
grants DEB-1145017 and DEB-1257545 to M.G.N. M.A.L.
also received support from the Canada Research Chair program
and a Killam Research Fellowship.
Description:
2016-08-06
Keywords:
Generational spreading speed
;
Stage structure
;
Invasion speed
;
Integrodifference models
;
Recolonization
;
Net reproductive number
;
Graph reduction
;
Next-generation operator
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
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