WHAT WE DO
The experimental ecology & conservation group focusses on synthesising information from mathematical models, small-scale experimental systems, and long-term wild population data to learn more about the world around us, and in particular help make decisions about how to best preserve biodiversity into the future.
A specific focus is on developing new, exciting, and useful techniques to make the experimental systems we work with more realistic reflections of the world around us.
ITS ALL ABOUT THE BIG PICTURE
But our focus is always on how we can learn more about the natural world without having to carry out invasive or damaging experiments in the field.
EARLY WARNING SIGNALS
Predicting the fate of biological systems is critical in the light of continued global change, especially in the field of conservation biology where at risk populations must be prioritised to make the most of limited resources. A long running interest of this group is developing warning signals of approach population, community, and ecosystem collapse based on temporal patterns in abundance, trait, and spatial data.
EXPERIMENTALLY TESTING CONSERVATION THEORY
Designing optimal conservation strategies is key in the face of limited funding and ever increasing anthropogenic stresses. A central theme to the group is using experimental systems to test and develop conservation theory.
TRACKING BIODIVERSITY CHANGE
Understanding whether biodiversity is changing is critical if we are to understand the impacts humanity is having on ecosystems, and whether management interventions are having the desired effects. Our group is working with Bristol City Council to produce a wildlife index to track biodiversity change in Bristol.
THE EFFECTS OF MULTIPLE STRESSORS
The effects of multiple stressors (e.g. including habitat loss, pollution, over harvesting, climatic change, and the introduction of invasive species) on global biodiversity is a continued concern. We are interested in the possible interactive effects of these stressors, and how this may affect populations and communities.
RESILIENCE AND RECOVERY IN FISHERIES
Fisheries are one of the most economic and ecologically important ecosystems on earth. However the vast majority are in a state of significant degradation. We are interested in how such systems might recovery, and the pathways they might take doing so, and how these pathways affect community structure and function.
DR CHRIS CLEMENTS
My interests centre on the extinction of species and collapse of populations, topics which I investigate using a combination of mathematical models, microcosm experiments, and analysis of real world population data.
My current interests are on resilience loss and the conservation of species in the face of multiple stressors.
DR FRANCESCO CERINI
Post doctoral researcher
My research interests are broad, but mainly revolving around abiotic factors and biotic interactions as structuring forces of species occurrence, distribution and abundance in ecosystems. Also, I am interested in studying the effects of human influence (e.g., habitat and climate modification, pollution, overharvesting) on ecosystem patterns and processes in a conservation framework. I both use local fieldwork data, macroecological approaches and experimental systems to test community assembly processes.
PhD student (University of Bristol)
I am studying the efficiency of wildlife corridors in theory and in practice. I am interested the role of corridors in determining the population growth and stability in microcosm networks and under field conditions, testing whether changing the quality and quantity of corridors can influence population dispersal ability and enhance ecosystem functions. My research would have a better understanding of the importance of wildlife corridors in fragmented habitats.
Co-supervised with Prof. Jane Memmott.
PhD Student (University of Bristol)
My MSc at the University of Essex has led to research interests involving the feedbacks of evolution and environment in shaping ecosystems and its management implications. I am a PhD student at the University of Bristol, exploring the use of early warning signals in predicting aquatic regime shifts via ecological modelling and analysis of long term data sets.
My background is in veterinary science, but my true passions lay in research and sustainable agricultural, particularly on how agricultural practices impact the environment. My PhD project investigates how agricultural drug residues influence on decomposer species diversity and abundance at a landscape level using computer simulations.
Co-supervised with Prof. Richard Wall
I am undertaking a Masters by Research in Global Environmental Challenges under the Environmental Change research theme. My research project will be investigating the impact(s) of multiple stressors, specifically climate change, overexploitation and habitat fragmentation, on ecological communities and the risk of extinction to their respective inhabitants. I have particular interests in marine conservation and management practices, sustainability and responses to environmental change. I will be using small-scale microcosm experiments and hope that it will inform discussion on conservation practices.
Ledger, S., McRae, L., Loh, J., Almond, R., Boh, M., Clements, C. et al. Past, present, and future of the Living Planet Index. npj Biodiversity, in press.
Wolfe, E., Cerini, F., Besson, M., O'Brien, D., Clements, C. Spatiotemporal thermal variation drives diversity trends in experimental landscapes. Journal of Animal Ecology, in press.
Backus, G., Clements, C., Baskett, M. Restoring local climate refugia to enhance the capacity for dispersal-limited species to track climate change. Pre print.
Johnson, T., Beckerman, A., Childs, D., Griffiths, C., Capdevila, P., Clements, C., Besson, M., Gregory, R., Evans, R., Thomas, G., Delmas, E., Webb, T., Freckleton, R. Overconfidence undermines global wildlife abundance trends. Pre print
O'Brien, D., Deb, S., Sahil, S., Krishnan, N., Dutta, P., Clements, C. EWSmethods: an R package to forecast tipping points at the community level using early warning signals and machine learning models. Pre print
Stewart, K., Carmona, C., Clements, C., Venditti, C., Tobias, J., González-Suárez, M. Trait diversity metrics can perform well with highly incomplete datasets. Pre print
Cerini, F., Childs, D., Clements, C. Timeline to collapse. Nature Ecology and Evolution, early online.
O'Brien, D., Gal, G., Thackary, S., Shin-Ichiro, S., Blanchard, J., Clements, C. Planktonic functional diversity changes in synchrony with lake ecosystem state. Global Change Biology, 29, 686-701.
Besson, M., Alison, J., Bjerge, J., Gorochowski, T., Høye, T., Jucker, T., Mann, H., Clements, C. Towards the fully automated monitoring of ecological communities. Ecology Letters, 25, 2753-2775.
Baruah, G., Ozgul, A., Clements, C. Community structure determines the predictability of population collapse. Journal of Animal Ecology, 91, 1880-1891.
Capdevila, P., Noviello, N., McRae, L., Freeman, R., Clements, C. Global patterns of resilience decline in vertebrate populations. Ecology Letters, 25 (1), 240-251.
Capdevila, P., Noviello, N., McRae, L., Freeman, R., Clements, C. Body mass and latitude as global predictors of vertebrate populations exposure to multiple threats. Ecography, 12, e06309.
Deb, S., Sidheekh, S., Clements, C., Krishnan, N., and Dutta, P. Machine learning methods trained on simple models can predict critical transitions in complex natural systems. Royal Society Open Science, 9: 211475.
Wolfe, E., Hammill, E., Memmott, J., Clements, C. Landscape configuration affects probability of apex predator presence and community structure in experimental metacommunities. Oecologia, 199, 193–204.
O'brien, D., Clements, C. Early warning signal reliability varies with COVID-19 waves. Biology Letters, 17: 20210487.
Williams, N., McRae, L., Freeman, R., Capdevila, P., Clements, C. Scaling the extinction vortex: Body size as a predictor of population dynamics close to extinction events. Ecology and Evolution, 11, 7069-7079.
Baruah, G., Clements, C., Ozgul, A. Effect of habitat quality and phenotypic variation on abundance- and trait-based early warning signals of population collapses. Oikos, 130, 850-862.
Li, D., Clements, C., Shan, I., Memmott, J. Corridor quality affects net movement, size of dispersers, and population growth in experimental microcosms. Oecologia 195, 547-556.
Arkilanian, A., Clements, C., Ozgul, A., Baruah, G. Effect of time-series length and resolution on abundance- and trait-based early warning signals of population declines. Ecology, in press.
Hammill, E., Clements, C. Imperfect detection alters the outcome of landscape scale management strategies for protected areas. Ecology Letters, 23: 682–691.
Baruah, G., Clements, C., Ozgul, A. Eco-evolutionary processes underlying early warning signals of population decline. Journal of Animal Ecology, 89:436–448.
Clements, C., McCarthy, M., Blanchard, J. Early warning signals of recovery in complex systems. Nature Communications, 10:1681.
Recommended by F1000
Baruah, G., Clements, C., Guillaume, F., Ozgul, A. When do shifts in trait dynamics precede population declines? The American Naturalist, 193, pp. 633–644.
Clements, C., Ozgul, A. Indicators of transitions in biological systems. Ecology Letters, 21, 905-919.
Recommended by F1000
Clements, C., Blanchard, J., Nash, K., Hindell, M., Ozgul, A. Reply to ‘Whaling catch data are not reliable for analyses of body size shifts’, Nature Ecology & Evolution, 2, 757–758.
Clements, C., Blanchard, J., Nash, K., Hindell, M., Ozgul, A. Body size shifts and early warning signals preceded the historic collapse of whale stocks. Nature Ecology & Evolution, 1, 188.
Carlson, C., Burgio, K., ... Clements, C., ... , Getz, W. (2017). Parasite biodiversity faces extinction and redistribution in a changing climate. Science Advances, 3, e1602422.
Weissman, T., Davies, K., Clements, C., Melbourne, B. Estimating extinction risk with minimal data. Biological Conservation, 213, 194-202.
Brooks, M., Clements, C., Pemberton, J., Ozgul, A. Estimation of individual growth trajectories when repeated measures are missing. American Naturalist, 190, 377-388.
Pimiento, C., Griffen, J., Clements, C., Silvestro, D., Varela, S., Uhen, M., Jaramillo, C. The Pliocene marine megafauna extinction and its impact on functional diversity. Nature Ecology & Evolution, 1, 1100.
Cizauskas, C., Carlson, C., Burgio, K., Clements, C., Dougherty, E., Harris, N., Phillips, A. (2017). Parasite vulnerability to climate change: an evidence-based functional trait approach.Royal Society Open Science, 4: 160535.
Clements, C., Ozgul, A. Rate of forcing and the forecastability of critical transitions. Ecology & Evolution, 6, 7787-7793.
Dougherty, E., Carlson, C., Bueno, V., Burgio, K., Cizauskas, C., Clements, C., Seidel, D., Harris, N. Paradigms for parasite conservation: adaptive approaches for a neglected target. Conservation Biology, 30, 724-733.
Pimiento, C., MacFadden, B., Clements, C., Velez-Juarbe, J., Jaramillo, C., Silliman, B. Geo- graphic distribution patterns of Carcharocles megalodon over time reveal clues about mechanisms of extinction. Journal of Biogeography, 43, 1645-1655.
Clements, C., Ozgul, A. Including trait-based early warning signals helps predict population collapse. Nature Communications, doi:10.1038/ncomms10984.
Clements, C., Drake, J., Griffiths, J., Ozgul, A. Factors influencing the detectability of early warning signals of population collapse. The American Naturalist, 186, 50-58.
DeLong, J., Gilbert, B., ..., Clements, C., ..., O'Connor, M. The body-size dependence of trophic cascades. The American Naturalist, 185, 354-366.
Palamara, G., Childs, D., Clements, C., Petchey, O., Plebani, M., Smith, M. Inferring the temperature dependence of population parameters: the effects of experimental design and inference algorithm. Ecology and Evolution, 4, 4567–4811.
McCarthy, M., Moore, A., Krauss, J., Morgan, J., Clements, C. Linking indices for biodiversity monitoring to extinction risk theory. Conservation Biology, 28, 1575-1583.
Pimiento C., Clements C. When did Carcharocles megalodon become extinct? A new analysis of the fossil record. PLoS ONE, DOI: 10.1371/journal.pone.0111086
Frantz, A., McDevitt, A., ..., Clements, C., ...., Burke, T. Re-visiting the phylogeography and demography of European badgers (Meles meles) based on broad sampling, multiple markers and simulations. Nature Heredity, 113, 443-453.
Clements, C., Collen, B., Blackburn, T., Petchey, O. Historic environmental change may affect our ability to infer extinction status. Conservation Biology, 28: 971–981.
Gilbert, B., Tunney, T., McCann, K., ..., Clements, C., ..., O’Connor, M. A bioenergetic framework for the temperature dependence of trophic interactions. Ecology Letters, 17, 902-914
Clements, C., Collen, B., Blackburn, T., Petchey, O. Effects of directional environmental change on extinction dynamics in experimental microbial communities are predicted by a simple model. Oikos, 123, 141-150
Clements, C., Warren, P., Collen, B., Blackburn, T., Worsfold, N., Petchey, O. Interactions between assembly order and temperature can alter both short and long-term community composition. Ecology & Evolution, 3(16): 5201–5208
Carlson, C., Cizauskas, C., Burgio, K., Clements, C., Harris, N. The more parasites, the better? Science, 342, p1041
Clements, C. Public interest in the extinction of a species may lead to an increase in donations to a large conservation charity. Biodiversity and Conservation, 22, p.2695-2699.
Clements, C., Worsfold, N., Warren, P., Collen, B., Blackburn, T., Clark, N., Petchey, O. Experimentally testing an extintion estimator: Solow's Optimal Linear Estmation model.Journal of Animal Ecology, 82, p345-354.
In line with the principals of open science and data sharing we are striving to make all the data that our lab group generates available via a github repository. This will take some time, but all data going forward will be uploaded to that site, and data from previous experiments (be that laboratory generated or simulation generated) will be made available as soon as possible.
EFFECTS OF MULTIPLE STRESSORS ON THE GLOBAL DECLINE OF VERTEBRATE POPULATIONS
2020 - 2022
JOIN THE GROUP
We are always looking for enthusiastic members to join the group, from masters students to post docs. Funding for these are available through a number of channels, depending on the career stage.
Please feel free to contact me any time to discuss the possibility of apply for one of these schemes and joining our team.
Adverts for funded positions will appear below
IS REWILDING A FEASIBLE LAND MANAGEMENT STRATEGY FOR THE UK?
Deadline: Friday 17th March 2023.
About the Project
Conservation and society are intimately linked; conservation cannot work without the support of societies, and societies can’t function without biodiverse ecosystems. However, biodiversity is continuing to decline, and consequently a new approach to conservation is needed. Rewilding (the restoration of degraded ecosystems through the reintroduction of missing species) has both grabbed and polarised the public, with research suggesting a suite of potential benefits: increasing biodiversity, stimulating local economies (e.g. through tourism), facilitating community health and engagement through access to green spaces, and increasing carbon sequestration. Thus, with careful planning of where and how rewilding is carried out, both biodiversity and deprived rural areas stand to benefit. However, to achieve this requires tensions between local stakeholders (e.g. farmers) and conservation proponents (e.g. rewilding charities) to be resolved. Building a roadmap to achieve this is fundamental for conservation to be successful across the UK over the coming decades, necessitating a strong focus on engaged local communities to improve health, wellbeing, and the environment for a sustainable planet.
This project consists of two linked PhD scholarships: one in social sciences (Human Geography) and one in ecology (Biology). These two PhD’s will run in parallel and feed results into one another, combining ecological habitat suitability modelling and a social survey, along with qualitative research, to identify areas of the UK where, and how, rewilding is both societally supported and ecologically possible. Doing so will:
Identify what areas of the UK provide the best initial sites for rewilding
Identify the best species to reintroduce into a given area to restore missing functions
Identify which areas have the greatest potential social and economic impact from rewilding
Understand the challenges and opportunities of rewilding, particularly the tensions and trade-offs with agriculture
Studentship 1 (Ecology, Biological Sciences)
Studentship one will focus on the ecological feasibility of rewilding in the UK. Working primarily with Dr Chris Clements, the student will use species distribution modelling, the student will (1) identify suitable habitat in the UK to reintroduce a range of species covering a range of ecological functions (from predators to ecosystem engineers), (2) identify potential rewilding hotspots – areas where multiple species can be simultaneously reintroduced into the same area, (3) incorporate economic data to identify which of these sites could have the greatest economic benefit to local areas, and (4) integrate the outputs from studentship 2 (social sciences) to give a holistic understanding where rewilding might have positive environmental and social impact.
Studentship 2 (Human Geography, School of Geographical Sciences)
Studentship Two will focus on the socio-cultural, political, and economic challenges and opportunities of rewilding in the UK. Working under the primary supervision of Dr Lauren Blake (Geographical Sciences), this project will explore the tensions and synergies between rewilding and food production/agriculture, including considering its viability, acceptability, and trade-offs. Policy analysis may also be relevant, as well as current trends towards regenerative and agroecological farming. The research will require primarily qualitative approaches (possibly including participatory/creative methods), but some quantitative methods will also be expected (e.g. survey data). As well as empirical, the PhD project should have strong theoretical grounding. The research will require integrating results from studentship 1 to give a holistic understanding of rewilding’s environmental and social potential and feasibility in the UK.
The project will require the postgraduate researcher to cultivate their autonomy over the project’s focus and trajectory. The successful student’s particular interests, background, experience, and expertise will heavily shape both the project focus and methodology accordingly. Applicants’ experience and ideas for moulding the potential of the research should be outlined in the application proposal.
The deadline to apply is Friday 17th March 2023. Interviews for shortlisted candidates are expected to take place during the weeks of 20th and 27th of March.