My main research interest lies in understanding individual-to-ecosystem level responses to environmental change, including warming, invasion, pollution and habitat loss. I am particularly interested in interactions among these stressors, and how stressor effects cascade through food webs with implications for ecosystem processes and services. I use a combination of field studies across both natural and anthropogenic stressor gradients, manipulative experiments and meta-analyses to seek general predictive rules in multiple stressor effects. Most of my research is in freshwater ecosystems, spanning from the Arctic to the tropics.
Influence of nutrient enrichment on the growth, recruitment and trophic ecology of a highly invasive freshwater fish
Food web properties vary with climate and land use in South African streams
Towards a unified study of multiple stressors: divisions and common goals across research disciplines.
Proc Biol Sci
Anthropogenic environmental changes, or 'stressors', increasingly threaten biodiversity and ecosystem functioning worldwide. Multiple-stressor research is a rapidly expanding field of science that seeks to understand and ultimately predict the interactions between stressors. Reviews and meta-analyses of the primary scientific literature have largely been specific to either freshwater, marine or terrestrial ecology, or ecotoxicology. In this cross-disciplinary study, we review the state of knowledge within and among these disciplines to highlight commonality and division in multiple-stressor research. Our review goes beyond a description of previous research by using quantitative bibliometric analysis to identify the division between disciplines and link previously disconnected research communities. Towards a unified research framework, we discuss the shared goal of increased realism through both ecological and temporal complexity, with the overarching aim of improving predictive power. In a rapidly changing world, advancing our understanding of the cumulative ecological impacts of multiple stressors is critical for biodiversity conservation and ecosystem management. Identifying and overcoming the barriers to interdisciplinary knowledge exchange is necessary in rising to this challenge. Division between ecosystem types and disciplines is largely a human creation. Species and stressors cross these borders and so should the scientists who study them.
antagonism, combined effects, global change factors, multiple drivers, multiple stressors, synergism, Biodiversity, Conservation of Natural Resources, Ecology, Ecosystem, Goals, Humans
Invasion syndromes: a systematic approach for predicting biological invasions and facilitating effective management
Bending the rules: exploitation of allochthonous resources by a top-predator modifies size-abundance scaling in stream food webs.
Body mass-abundance (M-N) allometries provide a key measure of community structure, and deviations from scaling predictions could reveal how cross-ecosystem subsidies alter food webs. For 31 streams across the UK, we tested the hypothesis that linear log-log M-N scaling is shallower than that predicted by allometric scaling theory when top predators have access to allochthonous prey. These streams all contained a common and widespread top predator (brown trout) that regularly feeds on terrestrial prey and, as hypothesised, deviations from predicted scaling increased with its dominance of the fish assemblage. Our study identifies a key beneficiary of cross-ecosystem subsidies at the top of stream food webs and elucidates how these inputs can reshape the size-structure of these 'open' systems.
Animals, Fishes, Ecosystem, Food Chain, Rivers
Between-lake variation in the trophic ecology of an invasive crayfish