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Dr Ian Vaughan

Dr Ian Vaughan

Senior Lecturer

+44 (0)29 2087 4545
Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX
Available for postgraduate supervision


My research focuses on the processes that shape communities over ecological and evolutionary timescales, and how they respond to environmental change. Much of this focusses upon river systems, for their rich diversity, importance and because they are an excellent model system for asking general ecological questions. This encompasses processes acting across a wide range of scales, from individual trophic interactions and food resource dynamics, through management interventions, land cover and fluvial geomorphology, to large-scale climatic effects. A variety of approaches is used to address these questions, including novel field studies, analysis of large data sets, null models, network analysis, experiments and molecular analyses.


Course Director: MSc Global Ecology and Conservation

Module Leader: BIT051 Assessing Biodiversity and Ecosystems


I read Biology at Bristol University (1997–2000) before making the trip over the Severn bridge to Cardiff to undertake a PhD (2000–4) with Prof. Steve Ormerod. The PhD focused on species distribution modelling, with river birds as a model system. Two years of post-doctoral work in Cardiff followed, contributing to the understanding of how ecology interacts with physical habitat in rivers.

In September 2006, I was awarded a Research Councils UK fellowship allowing me to pursue my research interests in river systems and quantitative methods, before moving onto a lectureship in September 2011. I was awarded a Cardiff University Research Leave Fellowship for the academic year (2016-17) and was a Visiting Research Scholar at the University of Vermont in 2016. In 2019, I moved onto a Senior Lectureship and established MSc Global Ecology and Conservation.






















Current projects include:

Long term changes in British rivers

Many UK rivers have changed greatly over recent decades. In and around urban areas, the news is often good, with large scale-recovery from historical water quality problems, albeit with ongoing issues. Elsewhere the news may be less positive, with stressors such as fine sediments and climate change becoming increasingly important. Work in this area has helped to elucidate the changes in river communities that have occurred, both nationally and more locally (e.g. Vaughan & Ormerod 2012, 2014; Phararoh et al. 2021), and whether the ecological benefits of water quality improvements have stalled.

Multiple stressor impacts on river ecosystems

Rivers are subjected to a range of stressors, including a cocktail of pollutants, alterations to the flow regime and a changing climate. The exposure varies among rivers and through time, and stressors may interact in different ways. Navigating this complexity is essential to better understand the effects of multiple stressors and to forecast how river ecosystems may respond to future changes in the mix of stressors. These are major themes of our NERC funded project ‘LTLS Freshwater Ecosystems: analysis and future scenarios of long-term and large-scale freshwater quality and impacts’ with UK-CEH, British Geological Survey, Rothamsted Research and Bowburn Consultancy.

Climate adaptation

Even with rapid reductions in greenhouse gas emissions, global temperatures will continue to rise for decades, making effective management strategies for reducing global change impacts a priority. Work in this area includes: i) characterising river ecosystems’ responses to climatic variation, and the ways in which riparian management may be able to increase their stability, and ii) the ways in which local management (e.g. improved water quality) can offset climate change via the concept of climatic credits (Vaughan & Gotelli, 2019, 2021).

Null model analysis of ecological networks

Null models are valuable tools for analysing community structure, and can help distinguish the roles of different processes in structuring ecological networks such as food webs and plant-pollinator networks. A fundamental question is the extent to which structure results from chance (e.g. interactions occur more frequently between common species than rare ones) as opposed to choice (e.g. dietary preferences). I wrote and maintain the econullnetr package for R (Vaughan et al. 2018), which provides a set of tools for running null models of ecological networks. My GitHub site hosts the most recent development version.

Current students (lead or co-supervisor)

  • Max Tercel: The effects of invasive ants on island food webs (NERC, with Durrell Wildlife Conservation Trust)
  • Fiona Joyce: Does riparian woodland increase the resilience of stream ecosystems to floods and droughts? (NERC, with Forest Research)
  • Emma Pharaoh: Diagnosing the reasons for biodiversity decline in rural rivers (NERC, with Natural Resources Wales, Environment Agency and UK Centre for Ecology and Hydrology)
  • Rachel Shepherd-Hunt (NERC) Long-term environmental influences on the ecology and conservation of river birds.
  • Maisie Brett, Bristol University (BBSRC, Bristol University): The potential for competition between managed honeybees and wild pollinators
  • Sophie Mallett (Cardiff University) Ant thermal biology at macroecological scales

Current/recent funding

  • NERC: LTLS Freshwater Ecosystems (LTLS-FE): Analysis and future scenarios of Long-Term and Large-Scale freshwater quality and impacts (with UK-CEH, British Geological Survey, Rothamsted Research and Bowburn Consultancy; total value £1.8m)
  • NERC: NETFRESH: Networking the response of freshwater ecosystems to environmental change (total value £80.6k) 
  • NERC: Diversity in upland rivers for ecosystem service sustainability (DURESS) project (total value £3.1m)
  • EU: Managing aquatic ecosystems and water resources under multiple stressors (MARS) project (total value €9m)

Other funders have included BBSRC, Natural Resources Wales and the Environment Agency.


Past projects

Jacqueline Platt (NERC, with Steve Ormerod): Habitat complexity and species diversity in rivers

Anna Bransden (with Fred Slater): The ecology of upland ponds in mid-Wales

Leila Duarte (with Rob Thomas): Impacts of capture and handling on wild birds

James Vafidis (EU, with Rob Thomas): The impacts of climate change on the ecology of a migrant wetland warbler

Joanna James (NRW/Cardiff University, with Jo Cable): The impacts of invasive crayfish on aquatic ecosystems

Caitlin Pearson (BBSRC, with Steve Ormerod and Bill Symondson): Effects of agricultural intensification on the ecology of upland stream invertebrate communities

Marian Pye (NERC/Cardiff University, with Isabelle Durance and Steve Ormerod): Catchment and riparian subsidy effects on upland stream ecosystems

Rhodri Thomas (President’s Research Scholarship, with Jose Constantine and Steve Ormerod): Predictions of river habitat response to climate change across the United Kingdom.

Danica Stark (Sime-Darby foundation, with Benoit Goossens): Fragment size, edge effects, and anthropogenic influences on the movement and distribution of proboscis monkeys (Nasalis larvatus) in the Kinabatangan Floodplain, Sabah

Jez Smith (NERC, with Rob Thomas and Hefin Jones): Impacts of climate change on pied flycatchers (Ficedula hypoleuca); from individual behaviour to population change

Jordan Cuff (BBSRC, with Bill Symondson and Pablo Orozco-terWengel): Nutrient-specific foraging and the role of spiders as aphid predators

Sarah Davies (NERC, with Bill Symondson and Rob Thomas): Projecting the effects of climate change on prey selection and dietary competition between reed bed warbler species

Richard Facey (with Rob Thomas): The effects of local weather variation on the seasonal fecundity of the barn swallow Hirundo rustica

Ewan Stenhouse (NERC, Pablo Orozco-terWengel and Bill Symondson): Is food availability and choice a limiting factor for declining UK Hawfinch populations?

Nick Tew (NERC, with Jane Memmott, Bristol University): Urban Buzz: quantifying and manipulating the resources available to pollinators in urban gardens.

Rebecca Young (NERC, with Bill Symondson and Jenny Dunn, University of Lincoln): Saving an iconic species from extinction in the UK: interactions between diet, parasites and environmental change

Mike Shewring (EU, with Rob Thomas). European Nightjar and upland plantation woodland management.

Richard Burger (with Benoit Goossens and Bill Symondson): Reticulated pythons in the Kinabatangan: coping with an altered landscape.

Rowena Diamond (EU, with Steve Ormerod and Rob Thomas): Diagnosing and mitigating the adverse effects of extreme winter climate on salmonid spawning