Contrasting ecological impacts of geographically close invasive populations
Intraspecific trait variability is now well recognized as a key component of biodiversity explaining how individuals within a species can differentially interact with their environment. To date, however, this concept has rarely been incorporated in the study of biological invasions, despite its provision of new insights into invasive species management. Here, we used an experimental approach to investigate how invasive red swamp crayfish (Procambarus clarkii) derived from geographically close ecosystems can differentially impact prey community structure and relevant ecosystem processes. We also compared the magnitude of the effects induced by invasive species introduction with those induced by intraspecific variability. Our results showed that effects of intraspecific variability can be strong for direct interactions such as resource (e.g., leaf litter, snails) consumption and of similar magnitude to the effects induced by the introduction of the invasive species when considering indirect interactions (e.g., primary production, ecosystem metabolism). Overall, these results highlighted that invasive populations of the same species are not ecologically equivalent, with each population acting differently on their recipient ecosystem.
KeywordsBiological invasions Intraspecific variation Ecosystem functioning Procambarus clarkii Ecological impacts
We are very grateful to Serge Boutes for access to the experiment site, and to Maria Alp, Rémy Lassus, Carine Rigolet and Libor Závorka for their help during the experiment. We also thank two anonymous reviewers and editors for their constructive comments on previous version of the manuscript.
Author contribution statement
CE, AL and JC conceived and designed the experiment. CE led the experiment. CE and AL performed the statistical analyses. CE, AL and JC wrote the manuscript.
This work was supported by the ONEMA (Projets ISOLAC and ERADINVA) and a PRES-Toulouse Grant (Inva_Eco_Evo_Lac).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
Authorizations to perform this study were provided by the “Arrêté Préfectoral—from 18/09/2015 to 30/10/2015”.
- Oksanen AJ, Blanchet FG, Kindt R et al (2017) Vegan: community ecology package. Version 2.4–3. http://CRAN.R-project.org/package=vegan
- Palkovacs EP, Fryxell DC, Turley NE, Post DM (2015) Ecological effects of intraspecific consumer biodiversity for aquatic communities and ecosystems. Aquatic functional biodiversity. Elsevier, Amsterdam, pp 37–51Google Scholar
- Petersen RC, Cummins KW (1974) Leaf processing in a woodland stream. Freshw Biol 4:343–368. https://doi.org/10.1111/j.1365-2427.1974.tb00103.x CrossRefGoogle Scholar
- R Development Core Team (2017) R: a language and environment for statistical computing. R Foundation for Statistical Computing, ViennaGoogle Scholar
- Steinman AD, Lamberti GA, Leavitt PR (2006) Biomass and pigments of benthic algae. Methods in stream ecology. Elsevier, Amsterdam, pp 357–379Google Scholar