Andrew Pledger

Dr Andrew Pledger

  • Research Associate
  • Fluvial Geomorphologist and Aquatic Ecologist

Academic career:

  • 2017 - present: Research associate (EPSRC Vaccinating the Nexus project), Loughborough University.
  • 2015 - 2017: Lecturer in Environmental Science, University Centre Reaseheath.

Professional responsibilities:

Andrew is a fluvial geomorphologist and aquatic ecologist interested in the physical processes at work in rivers, the habitats they create, and how these influence and are influenced by freshwater biota. Simultaneously, his research critically evaluates methods of and strategies for sustainable management of environmental systems. Knowledge in these areas is important for developing greater understanding of how environmental systems work and can be used to inform management strategies. Within these and other themes, his research to-date predominately follows five strands:

1. Environmental consequences of river/catchment management methods (e.g. dredging, weir removal), including work with the Somerset Drainage Boards Consortium, Environment Agency, Van Oord UK and Nottingham University. 

2. Ecosystem engineering and freshwater zoogeomorphology – how animals (predominately rheophilic cyprinid fish) affect fluvial sediment transport processes, including work with the Barbel Society.

3. Spawning gravels… a barrier to recruitment? – includes incubation experiments to quantify specific tolerances of fish eggs and larvae to different environmental pressures. In collaboration with Fishmongers’ Company, Environment Agency and the Barbel Society.

4. Critique of fish spawning habitat restoration methods (e.g. gravel jetting), including work with Bournemouth university, Environment Agency and the Barbel Society.

5. Angling activities and their impacts on freshwater ecosystems – includes fish diet and development studies in collaboration with Bournemouth University and the Barbel Society.

Andrew's teaching examines the feedback loops between present and future fish populations, their habitat, and physical and ecological processes. Andrew contributes to learning and teaching activities in undergraduate and postgraduate geography programmes through a mix of lectures, laboratories and field courses.


  • Remote Sensing and GIS (GYB201)
  • Environmental Hazards: from Mitigation to Management (GYA112)


  • Applied Environmental GIS (GYD029, GYP029)
  • Natural Hazard and Catastrophe Modelling for Environmental Management (GYD036; GYP036)

Current postgraduate research students

  • James Champkin: Spawning habitat characteristics of lithophilic fish – using experimental approaches to inform river restoration.

Recent postgraduate research students

  • Gutmann Roberts, Bašić T, Britton RJ, Rice S, Pledger AG (2019) Quantifying the habitat and zoogeomorphic capabilities of spawning European barbel Barbus barbus, a lithophilous cyprinid. River Research and Applications, 1-21. DOI: 10.1002/rra.3573.   
  • Rice, SP, Pledger, AG, Toone, J, Mathers, K (2019) Zoogeomorphological behaviours in fish and the potential impact of benthic foraging on bed material mobility in fluvial landscapes. Earth Surface Processes and Landforms, 44, 54-66. DOI: 10.1002/esp.4541.    
  • Bašić T, Britton R, Rice SP, Pledger AG (2018) Sand content in spawning substrate as a driver of early larval emergence in a lithophilic cyprinid fish, Accepted: Ecology of Freshwater Fish. DOI: 10.1111/eff.12435.     
  • Bašić, T, Britton, JR, Rice, SP, Pledger, AG (2017) Impacts of gravel jetting on the composition of fish spawning substrates: Implications for river restoration and fisheries management, Ecological Engineering, 107, pp.71-81, ISSN: 0925-8574. DOI: 10.1016/j.ecoleng.2017.06.057.
  • Pledger, AG, Rice, SP, Millett, J (2017) Foraging Fish as Zoogeomorphic Agents: An Assessment of Fish Impacts at Patch, Barform, and Reach Scales, Journal of Geophysical Research: Earth Surface, 122(11), pp.2105-2123, ISSN: 2169-9003. DOI: 10.1002/2017JF004362.
  • Pledger, AG, Rice, SP, Millett, J (2015) Bed disturbance via foraging fish increases bedload transport during subsequent high flows and is controlled by fish size and species, Geomorphology, 253, pp.83-93, ISSN: 1872-695X. DOI: 10.1016/j.geomorph.2015.09.021.     
  • Pledger, AG, Rice, SP, Millett, J (2014) Reduced bed material stability and increased bedload transport caused by foraging fish: A flume study with juvenile Barbel (Barbus barbus), Earth Surface Processes and Landforms, 39(11), pp.1500-1513, ISSN: 0197-9337. DOI: 10.1002/esp.3592.