Acclimation effects on thermal tolerances of springtails from sub-Antarctic Marion Island: indigenous and invasive species

Slabber, S., Worland, M. R., Leinaas, H. P., & Chown, S. L. (2007). Acclimation effects on thermal tolerances of springtails from sub-Antarctic Marion Island: indigenous and invasive species. Journal of Insect Physiology, 53(2), 113-125. PDF.

Summary

Few organisms possess the physiological flexibility (i.e. “plasticity”) to withstand the harsh environment of Antarctica. Springtails (Collembola sp.) are some of the few arthropods adapted to these conditions, and  they play an important ecological role in these terrestrial ecosystems threatened by climate change. Not only will the physiological tolerances of native springtails be challenged by climate warming, but the introduction of exotic springtails also threatens to displace native relatives. To explore the effects of warming on springtails of different origins living in Antarctica, Slabber et al. (2007) compared the high and low thermal tolerances of three invasive (Pogonognathellus flavescens, Isotomurus cf. palustris, Ceratophysella denticulate) and two native springtails (Cryptopygus antarcticus travei, Tullbergia bisetosa). The authors found that the invasive arthropods, which are adapted to a warmer European climate, persist in warmer microhabitats in Antarctica and have higher thermal tolerances than the native springtails. This suggests that the invasives will have a competitive and physiological advantage over the natives under climate warming. Conversely, native species in this study showed evidence of acclimating to warmer temperatures and retained their cold tolerance throughout the experiments. This plastic response to temperature variation indicates that native springtails are likely to persist in Antarctica and continue their role as detritivores, but there is still potential for loss of native biodiversity as invasive springtails survive warming temperatures and possibly displace cold-adapted native species.

Take home points

• Climate change impacts will likely favor organisms that show plasticity (i.e. flexible physiological responses) to varying temperatures.

• As global warming continues, invasive species from warmer climates have a physiological advantage over native species adapted to present climate conditions.

Management implications

• Identifying the source location of invasive species can help prioritize management of warm-adapted invasive species that show potential to thrive under climate warming.

• Invasive species may displace native relatives (i.e. native species of the same functional group) if they share similar ecological niches but display higher tolerances to environmental changes and extreme events.

Keywords

Competitiveness; Experiment; Invasive Invertebrate; Terrestrial Habitat; Risk Assessment