Corridor quality buffers extinction under extreme droughts in experimental metapopulations

• Published in: Ecology and evolution Vol. 13; no. 6; pp. e10166 - n/a
• Main Authors: Li, Dongbo, Memmott, Jane, Clements, Christopher F.
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.06.2023; John Wiley and Sons Inc
• Subjects: Buffers; climate change; Conservation Ecology; Corridors; Dispersal; Drought; drought severity; ecological traps; Endangered & extinct species; Environmental changes; environmental stressors; Extinction; Extreme drought; Habitat corridors; habitat fragmentation; Habitats; Humidity; Metapopulations; perturbations; Populations; Species extinction; Time measurement; Variability; Water shortages; wildlife corridors; ecological traps; environmental stressors; wildlife corridors; perturbations; drought severity; climate change; habitat fragmentation
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.10166

Corridors with good‐quality habitats maintain the spatial dynamics of metapopulations by promoting dispersal between habitat patches, potentially buffering populations, and communities against continued global change. However, this function is threatened by habitats becoming increasingly fragmented, and habitat matrices becoming increasingly inhospitable, potentially reducing the resilience and persistence of populations. Yet, we lack a clear understanding of how reduced corridor quality interacts with rates of environmental change to destabilize populations. Using laboratory microcosms containing metapopulations of the Collembola Folsomia candida, we investigate the impact of corridor quality on metapopulation persistence under a range of simulated droughts, a key stressor for this species. We manipulated both drought severity and the number of patches affected by drought across landscapes connected by either good‐ or poor‐quality corridors. We measured the time of metapopulation extinction, the maximum rate of metapopulation decline, and the variability of abundance among patches as criteria to evaluate the persistence ability of metapopulations. We show that while drought severity negatively influenced the time of metapopulation extinction and the increase in drought patches caused metapopulation decline, these results were mitigated by good‐quality corridors, which increased metapopulation persistence time and decreased both how fast metapopulations declined and the interpatch variability in abundances. Our results suggest that enhancing corridor quality can increase the persistence of metapopulations, increasing the time available for conservation actions to take effect, and/or for species to adapt or move in the face of continued stress. Given that fragmentation increases the isolation of habitats, improving the quality of habitat corridors may provide a useful strategy to enhance the resistance of spatially structured populations. Corridors maintain the spatial dynamics of metapopulations by promoting dispersal between habitat patches, potentially buffering populations and communities against continued global change. Using a lab microcosm experiment, we demonstrate how corridor quality maintains the persistence of metapopulations in the face of extreme climate change.