Central-marginal population dynamics in species invasions

Abstract

The species' range limits and associated central-marginal (C-M, i.e., from species range center to margin) population dynamics continue to draw increasing attention because of their importance for current emerging issues such as biotic invasions and epidemic diseases under global change. Previous studies have mainly focused on species borders and C-M process in natural settings for native species. More recently, growing efforts are devoted to examine the C-M patterns and process for invasive species partly due to their relatively short history, highly dynamic populations, and management implications. Here I examine recent findings and information gaps related to (1) the C-M population dynamics linked to species invasions, and (2) the possible effects of climate change and land use on the C-M patterns and processes. Unlike most native species that are relatively stable (some even having contracting populations or ranges), many invasive species are still spreading fast and form new distribution or abundance centers. Because of the strong nonlinearity of population demographic or vital rates (i.e., birth, death, immigration, and emigration) across the C-M gradients and the increased complexity of species ranges due to habitat fragmentation, multiple introductions, range-wide C-M comparisons and simulation involving multiple vital rates are needed in the future.

Is the raccoon (Procyon lotor) out of control in Europe?

“…Therefore, a large central expanding (core) and other small marginal isolated (border) patches determine a disjunct spatial distribution pattern, typical of species invasions (Guo 2014).…”

Global trade will accelerate plant invasions in emerging economies under climate change

“…The role environmental variability plays in the macroecology of biological invasions remains to be analyzed in subsequent studies. It has to be noted that the predicted numbers of naturalized plants represent mean values averaged across the entire distribution of a species, although in nature the dynamics are more complex due to central-marginal population dynamics (Guo, 2014). At the center of a species' distribution, the density tends to be high and, thus, a population is more robust against disturbances compared to a population at range margins, where densities are lower.…”

Mixed population genomics support for the central marginal hypothesis across the invasive range of the cane toad (Rhinella marina) in Australia

“…Although unfortunate, species invasions provide unique opportunities to test hypotheses for the evolution of species' range limits (Sexton et al 2009;Guo 2014). However, one challenge in testing species' range limit theory is the identification of core and edge regions, particularly in invasive species that have large, noncircular geographic ranges that still expanding (Hoffmann & Blows 1994;Sexton et al 2009;Micheletti & Storfer 2015).…”

“…Species invasions provide unique, albeit unfortunate, opportunities to test evolutionary hypotheses for species' geographic range limits (Sexton et al . ; Guo ). The cane toad ( Rhinella [ Bufo ] marina ) (Linnaeus, 1758; Pramuk et al .…”

“…Species invasions provide unique, albeit unfortunate, opportunities to test evolutionary hypotheses for species' geographic range limits (Sexton et al 2009;Guo 2014). The cane toad (Rhinella [Bufo] marina) (Linnaeus, 1758;Pramuk et al 2007), native to tropical and subtropical habitats in the Americas, has become a notorious worldwide invader (Lever 2001;Kraus 2009;www.issg.org).…”