Stephen Gregory

Dr Stephen Gregory

  • Senior Statistician
  • Centre for Environment Fisheries and Aquaculture Science (Cefas)
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I am a conservation biologist. I use population modelling to understand and propose management actions to conserve animal populations under global change, from native Galapagos rodents to Malaysian orangutans. My research has included fisheries metapopulation modelling, spatial population dynamics and effects of connectivity, susceptibility of social species (particularly bats) to Allee effects, and effects of Allee effects on population extinction dynamics.

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Journal Articles

  • Tréhin, C., Gregory, S.D. et al., 2024. A multi-population approach supports common patterns in marine growth and maturation decision in Atlantic salmon (Salmo salar L.) from southern Europe. Journal of Fish Biology, 104 (1), 125-138.
  • Birch, S.F., Gregory, S.D., Maxwell, D.L., Desender, M. and Catchpole, T.L., 2023. How an illuminated headline affects catches and species separation in a Celtic Sea mixed demersal trawl fishery. Fisheries Research, 268.
  • Gregory, S.D. et al., 2023. Estimation of returning Atlantic salmon stock from rod exploitation rate for principal salmon rivers in England & Wales. ICES Journal of Marine Science, 80 (10), 2504-2519.
  • Artero, C., Gregory, S.D., Beaumont, W.A., Josset, Q., Jeannot, N., Cole, A., Lamireau, L., Reveillac, E. and Lauridsen, R.B., 2023. Survival of Atlantic salmon and sea trout smolts in transitional waters. Marine Ecology: Progress Series, 709, 91-108.
  • Simmons, O.M., Britton, J.R., Gillingham, P.K., Nevoux, M., Riley, W.D., Rivot, E. and Gregory, S.D., 2022. Predicting how environmental conditions and smolt body length when entering the marine environment impact individual Atlantic salmon Salmo salar adult return rates. Journal of Fish Biology, 101 (2), 378-388.
  • Bull, C.D., Gregory, S.D., Rivot, E., Sheehan, T.F., Ensing, D., Woodward, G. and Crozier, W., 2022. The likely suspects framework: The need for a life cycle approach for managing Atlantic salmon (Salmo salar) stocks across multiple scales. ICES Journal of Marine Science, 79 (5), 1445-1456.
  • Marsh, J.E., Cove, R.J., Britton, J.R., Wellard, R.G., Bašić, T. and Gregory, S.D., 2022. Density-dependence and environmental variability have stage-specific influences on European grayling growth. Oecologia, 199 (1), 103-117.
  • Marsh, J.E., Lauridsen, R.B., Gregory, S.D., Kratina, P., Scott, L.J., Cooling, D. and Jones, J.I., 2022. High summer macrophyte cover increases abundance, growth, and feeding of juvenile Atlantic salmon. Ecological Applications, 32 (2).
  • Marsh, J.E., Gregory, S.D. et al., 2021. Warm winters and cool springs negatively influence recruitment of Atlantic salmon (Salmo salar L.) in a southern England chalk stream. Journal of Fish Biology, 99 (3), 1125-1129.
  • Marsh, J.E., Cove, R.J., Britton, J.R., Wellard, R.G., House, A. and Gregory, S.D., 2021. Medium-term environmental changes influence age-specific survival estimates in a salmonid population. Freshwater Biology, 66 (8), 1530-1545.
  • Simmons, O.M., Gregory, S.D., Gillingham, P.K., Riley, W.D., Scott, L.J. and Britton, J.R., 2021. Biological and environmental influences on the migration phenology of Atlantic salmon Salmo salar smolts in a chalk stream in southern England. Freshwater Biology, 66 (8), 1581-1594.
  • Tréhin, C., Rivot, E., Lamireau, L., Meslier, L., Besnard, A.L., Gregory, S.D. and Nevoux, M., 2021. Growth during the first summer at sea modulates sex-specific maturation schedule in atlantic salmon. Canadian Journal of Fisheries and Aquatic Sciences, 78 (6), 659-669.
  • Gillson, J.P., Maxwell, D.L., Gregory, S.D., Posen, P.E., Riley, W.D., Picken, J.L. and Assunção, M.G.L., 2020. Can aspects of the discharge regime associated with juvenile Atlantic salmon (Salmo salar L.) and trout (S. trutta L.) densities be identified using historical monitoring data from five UK rivers? Fisheries Management and Ecology, 27 (6), 567-579.
  • Gregory, S.D., Bewes, V.E., Davey, A.J.H., Roberts, D.E., Gough, P. and Davidson, I.C., 2020. Environmental conditions modify density-dependent salmonid recruitment: Insights into the 2016 recruitment crash in Wales. Freshwater Biology, 65 (12), 2135-2153.
  • Simmons, O.M., Britton, J.R., Gillingham, P.K. and Gregory, S.D., 2020. Influence of environmental and biological factors on the overwinter growth rate of Atlantic salmon Salmo salar parr in a UK chalk stream. Ecology of Freshwater Fish, 29 (4), 665-678.
  • Marsh, J.E., Lauridsen, R.B., Gregory, S.D., Beaumont, W.R.C., Scott, L.J., Kratina, P. and Jones, J.I., 2020. Above parr: Lowland river habitat characteristics associated with higher juvenile Atlantic salmon (Salmo salar) and brown trout (S. trutta) densities. Ecology of Freshwater Fish, 29 (4), 542-556.
  • Gregory, S.D., Britton, J.R., Gillingham, P.K. et al., 2019. Atlantic salmon return rate increases with smolt length. ICES Journal of Marine Science, 76 (6), 1702-1712.
  • Bašić, T., Britton, J.R., Cove, R.J., Ibbotson, A.T. and Gregory, S.D., 2018. Roles of discharge and temperature in recruitment of a cold-water fish, the European grayling Thymallus thymallus, near its southern range limit. Ecology of Freshwater Fish, 27 (4), 940-951.
  • Riley, W.D., Ibbotson, A.T., Gregory, S.D., Russell, I.C., Lauridsen, R.B., Beaumont, W.R.C., Cook, A.C. and Maxwell, D.L., 2018. Under what circumstances does the capture and tagging of wild Atlantic salmon Salmo salar smolts affect probability of return as adults? Journal of Fish Biology, 93 (3), 477-489.
  • Gregory, S.D., Armstrong, J.D. and Britton, J.R., 2018. Is bigger really better? Towards improved models for testing how Atlantic salmon Salmo salar smolt size affects marine survival. Journal of Fish Biology, 92 (3), 579-592.
  • Angulo, E., Luque, G.M., Gregory, S.D., Wenzel, J.W., Bessa-Gomes, C., Berec, L. and Courchamp, F., 2018. Allee effects in social species. Journal of Animal Ecology, 87 (1), 47-58.
  • Parry, E.S., Gregory, S.D., Lauridsen, R.B. and Griffiths, S.W., 2018. The effects of flow on Atlantic salmon (Salmo salar) redd distribution in a UK chalk stream between 1980 and 2015. Ecology of Freshwater Fish, 27 (1), 128-137.
  • Gregory, S.D., Nevoux, M., Riley, W.D., Beaumont, W.R.C., Jeannot, N., Lauridsen, R.B., Marchand, F., Scott, L.J. and Roussel, J.M., 2017. Patterns on a parr: Drivers of long-term salmon parr length in U.K. and French rivers depend on geographical scale. Freshwater Biology, 62 (7), 1117-1129.
  • Harris, D.B., Gregory, S.D., Brook, B.W., Ritchie, E.G., Croft, D.B., Coulson, G. and Fordham, D.A., 2014. The influence of non-climate predictors at local and landscape resolutions depends on the autecology of the species. Austral Ecology, 39 (6), 710-721.
  • Gregory, S.D., Ancrenaz, M., Brook, B.W., Goossens, B., Alfred, R., Ambu, L.N. and Fordham, D.A., 2014. Forecasts of habitat suitability improve habitat corridor efficacy in rapidly changing environments. Diversity and Distributions, 20 (9), 1044-1057.
  • Harris, J.B.C., Dwi Putra, D., Gregory, S.D., Brook, B.W., Prawiradilaga, D.M., Sodhi, N.S., Wei, D. and Fordham, D.A., 2014. Rapid deforestation threatens mid-elevational endemic birds but climate change is most important at higher elevations. Diversity and Distributions, 20 (7), 773-785.
  • Haby, N.A., Prowse, T.A.A., Gregory, S.D., Watts, M.J., Delean, S., Fordham, D.A., Foulkes, J. and Brook, B.W., 2013. Scale dependency of metapopulation models used to predict climate change impacts on small mammals. Ecography, 36 (7), 832-841.
  • Bradshaw, C.J.A., Gregory, S.D. et al., 2013. Brave new green world - Consequences of a carbon economy for the conservation of Australian biodiversity. Biological Conservation, 161, 71-90.
  • Gregory, S.D., Brook, B.W., Goossens, B., Ancrenaz, M., Alfred, R., Ambu, L.N. and Fordham, D.A., 2012. Long-Term Field Data and Climate-Habitat Models Show That Orangutan Persistence Depends on Effective Forest Management and Greenhouse Gas Mitigation. PLoS ONE, 7 (9).
  • Harris, D.B., Gregory, S.D., Bull, L.S. and Courchamp, F., 2012. Island prioritization for invasive rodent eradications with an emphasis on reinvasion risk. Biological Invasions, 14 (6), 1251-1263.
  • Gregory, S. and Jones, G., 2010. Bats and Allee effects: When social behaviours go batty. Biologist, 57 (4), 198-205.
  • Gregory, S.D., Bradshaw, C.J.A., Brook, B.W. and Courchamp, F., 2010. Limited evidence for the demographic Allee effect from numerous species across taxa. Ecology, 91 (7), 2151-2161.
  • Gregory, S.D. and Courchamp, F., 2010. Safety in numbers: Extinction arising from predator-driven Allee effects. Journal of Animal Ecology, 79 (3), 511-514.
  • Gregory, S.D. and MacDonald, D.W., 2009. Prickly coexistence or blunt competition? Opuntia refugia in an invaded rodent community. Oecologia, 159 (1), 225-236.
  • Gascoigne, J., Berec, L., Gregory, S. and Courchamp, F., 2009. Dangerously few liaisons: A review of mate-finding Allee effects. Population Ecology, 51 (3), 355-372.
  • Harris, D.B., Gregory, S.D. and Macdonald, D.W., 2006. Space invaders? A search for patterns underlying the coexistence of alien black rats and Galápagos rice rats. Oecologia, 149 (2), 276-288.