The scaling of population persistence with carrying capacity does not asymptote in populations of a fish experiencing extreme climate variability
| Autor: | Brendan A. Wintle, Angus R. McIntosh, D.J. Booker, Peter A. McHugh, Richard S. A. White |
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| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Conservation of Natural Resources 010504 meteorology & atmospheric sciences Climate Population Population Dynamics Climate change Metapopulation 010603 evolutionary biology 01 natural sciences General Biochemistry Genetics and Molecular Biology Carrying capacity Animals education 0105 earth and related environmental sciences General Environmental Science Population Density education.field_of_study Extinction Global Change and Conservation General Immunology and Microbiology Ecology Global warming Fishes Small population size General Medicine Geography Habitat destruction General Agricultural and Biological Sciences |
| Zdroj: | Proceedings. Biological sciences. 284(1856) |
| ISSN: | 1471-2954 |
| Popis: | Despite growing concerns regarding increasing frequency of extreme climate events and declining population sizes, the influence of environmental stochasticity on the relationship between population carrying capacity and time-to-extinction has received little empirical attention. While time-to-extinction increases exponentially with carrying capacity in constant environments, theoretical models suggest increasing environmental stochasticity causes asymptotic scaling, thus making minimum viable carrying capacity vastly uncertain in variable environments. Using empirical estimates of environmental stochasticity in fish metapopulations, we showed that increasing environmental stochasticity resulting from extreme droughts was insufficient to create asymptotic scaling of time-to-extinction with carrying capacity in local populations as predicted by theory. Local time-to-extinction increased with carrying capacity due to declining sensitivity to demographic stochasticity, and the slope of this relationship declined significantly as environmental stochasticity increased. However, recent 1 in 25 yr extreme droughts were insufficient to extirpate populations with large carrying capacity. Consequently, large populations may be more resilient to environmental stochasticity than previously thought. The lack of carrying capacity-related asymptotes in persistence under extreme climate variability reveals how small populations affected by habitat loss or overharvesting, may be disproportionately threatened by increases in extreme climate events with global warming. |
| Databáze: | OpenAIRE |
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