Predators mitigate the destabilising effects of heatwaves on multitrophic stream communities
Ross, S.R.P.-J.; García Molinos, J.; Okuda, A.; Johnstone, J.; Atsumi, K.; Futamura, R.; Williams, M.A.; Matsuoka, Y.; Uchida, J.; Kumikawa, S.; Sugiyama, H.; Kishida, O.; Donohue, I. (2021). Predators mitigate the destabilising effects of heatwaves on multitrophic stream communities. Glob. Chang. Biol. 28(2): 403-416. https://dx.doi.org/10.1111/gcb.15956
In: Global Change Biology. Blackwell Publishers: Oxford. ISSN 1354-1013; e-ISSN 1365-2486, more
|  |
| Keywords |
Biodiversity
Climate Change
|
| Author keywords |
ecological stability, extreme events, food web, heatwaves, Horonai stream, spatial variability, temporal variability |
| Authors | | Top |
- Ross, S.R.P.-J.
- García Molinos, J.
- Okuda, A.
- Johnstone, J.
- Atsumi, K.
|
- Futamura, R.
- Williams, M.A.
- Matsuoka, Y.
- Uchida, J.
|
- Kumikawa, S.
- Sugiyama, H.
- Kishida, O.
- Donohue, I.
|
| Abstract |
Amidst the global extinction crisis, climate change will expose ecosystems to more frequent and intense extreme climatic events, such as heatwaves. Yet, whether predator species loss—a prevailing characteristic of the extinction crisis—will exacerbate the ecological consequences of extreme climatic events remains largely unknown. Here, we show that the loss of predator species can interact with heatwaves to moderate the compositional stability of ecosystems. We exposed multitrophic stream communities, with and without a dominant predator species, to realistic current and future heatwaves and found that heatwaves destabilised algal communities by homogenising them in space. However, this happened only when the predator was absent. Additional heatwave impacts on multiple aspects of stream communities, including changes to the structure of algal and macroinvertebrate communities, as well as total algal biomass and its temporal variability, were not apparent during heatwaves and emerged only after the heatwaves had passed. Taken together, our results suggest that the ecological consequences of heatwaves can amplify over time as their impacts propagate through biological interaction networks, but the presence of predators can help to buffer such impacts. These findings underscore the importance of conserving trophic structure, and highlight the potential for species extinctions to amplify the effects of climate change and extreme events. |
|
