As climate change continues, species are likely to respond directly to changes in multiple environmental conditions and indirectly to shifts in species interactions. We have been using novel, field-based approaches to simulate warming and CO2 enrichment in tide pool systems in collaboration with the Bracken Lab at UCI. Results from a short-term experiment suggest that warming and CO2 interact to influence productivity of these systems and that this ecosystem-level response emerges before any changes to community composition.
Will climate change increase the impact of invasive species?
Invasive species have had large ecological and economic impacts worldwide and, with climate change, are one of the primary threats to global biodiversity. Impacts tend to increase with range size, population size, and strength of per capita effects, all of which could be altered by changing climatic conditions. We are addressing the potential for climate change to increase invasive species impacts in an international working group (led by Dr. Sorte and funded by the Borchard Foundation) that met in in June 2015 and May 2016. This work follows on the findings of an NCEAS working group, described below.
Dr. Sorte’s Ph.D. dissertation research addressed the hypothesis that climate change will favor non-native species. She took a demographic approach to address the impacts of ocean warming on the relative abundance of native and non-native species in a subtidal epibenthic community. Results of historical comparisons, field observations, lab mesocosm experiments, and population and competition modeling indicated that non-natives are likely to become even more dominant in this study system as ocean warming continues.
Work conducted in collaboration with graduate student advisees further increased understanding of the links between climate change and invasions in this system. Robyn Zerebecki’s comparisons showed that habitat temperatures were correlated with temperature tolerances of these epibenthic species, supporting a mechanism translating tolerances into geographic ranges, invasion success, and resistance to warming climate. Simulation experiments with Adam Fuller indicated that heat waves have the potential to cause abrupt increases in the relative abundance of non-native species. Finally, Marcy Cockrell demonstrated the utility of demographic population modeling for predicting climate effects on non-natives’ population sizes.
We addressed this question in a cross-ecosystem context as part of a National Center for Ecological Analysis and Synthesis working group (led by Dr. Sorte, Jeff Dukes – Purdue U., and Josh Lawler – UW). Products from this group included: (1) the first cross-ecosystem meta-analysis of climate change effects on performance of native versus non-native species, (2) a review of the impacts of extreme events on biological invasions, (3) an analysis of how climate change affects invasion potential via the horticulture trade, (4) an integrative framework for predicting invasion potential, and (5) a comparison of range dynamics of native and non-native plants in the USA.