Callum Macgregor

Senior Research Ecologist

Callum works as a Senior Research Ecologist analysing quantitative data from a range of projects from Wales.

Interests & Responsibilities

Callum’s interests as an ecologist are broad, but centre on how organisms (at individual, population and community scales) respond to changes in their environment, especially when those changes are induced by human activity.

He completed his PhD at Newcastle University, studying how light pollution at night affects the role of moths as pollinators, and undertook two subsequent postdoctoral research positions in Yorkshire investigating the impacts of climate change on butterflies (York) and the ecological value of brownfield sites to birds, plants, and insects (Hull) respectively, before joining the BTO in May 2021.

Callum is based within the BTO Cymru office looking at Welsh bird populations and their conservation.

Qualifications

BA (Hons.) Biological Sciences, University of Oxford, 2013.
PhD Ecology: “The role of moths as pollinators, and the effects of environmental change”, Newcastle University, 2017.

Recent BTO Publications

Macgregor, C.J., Pearce-Higgins, J.W., Siriwardena, G.M., Wilson, M.W. & Robinson, R.A. 2025. Assessment of recent Hen Harrier population trends in England through population modelling. Research Report no. 778. BTO Research Report 778 British Trust for Ornithology, Thetford, UK ISBN: 978-1-912642-75-5 30pp

Hereward, H.F.R., Brenchley, A., Facey, R.J., Hughes, J., Lindley, P.J., Taylor, R.C., Wilson, M.W. & Macgregor, C.J. 2025. Status and distribution of Rook Corvus frugilegus in Wales in 2022/23. Milvus 3 : 32-50 Link to publication

Macgregor, C.J., Gillings, S., Balmer, D.E., Boersch-Supan, P.H., Harris, S.J., Hereward, H.F.R., Humphreys, E.M., Pearce-Higgins, J.W., Taylor, R.C., Troost, G. & Atkinson, P.W. 2024. Impacts of highly pathogenic avian influenza on seabird populations in the North Sea are detectable in sea-watchers’ migration counts. Bird Study View at journal website (DOI: 10.1080/00063657.2024.2440826)

Hereward, H.F.R., Macgregor, C.J., Gabb, O., Connell, A., Thomas, R.J., Cross A.V. & Taylor, R.C. 2024. Modelling population‐level impacts of wind farm collision risk on Welsh Red Kites. Milvus 3 : 75-99 Link to publication

Hereward, H.F.R., Macgregor, C.J., Gabb, O., Connell, A., Thomas, R.J., Cross, A.V. & Taylor, R.C. 2024. Modelling population-level impacts of wind farm collision risk on Welsh Red Kites. Research Report no. 766. British Trust for Ornithology, Thetford

Kenobi, K., Read, W., Bowgen, K., Macgregor, C., Taylor, R., Cámaro García, W., Hodges, C., Dennis, P. & Holloway, P. 2023. Lasso Penalisation identifies consistent trends over time in landscape and climate factors influencing the wintering distribution of the Eurasian Curlew (Numenius arquata). Ecological Informatics View at journal website (DOI: 10.1016/j.ecoinf.2023.102244)

Other Publications

E.D. Taylor-Cox, C.J. Macgregor, A. Corthine, J.K. Hill, J.A. Hodgson and I.J. Saccheri (2020) Wing morphological responses to latitude and colonisation in a range expanding butterfly. PeerJ, doi: 10.7717/peerj.10352.

R.S. Kinsella, C.D. Thomas, T.J. Crawford, J.K. Hill, P.J. Mayhew and C.J. Macgregor* (2020) Unlocking the potential of historical abundance datasets to study biomass change in flying insects. Ecology and Evolution, 10, 8394–8404. *corresponding author

C.J. Macgregor and A.S. Scott-Brown (2020) Nocturnal pollination: An overlooked ecosystem service vulnerable to environmental change. Emerging Topics in Life Sciences, 4, 19–32.

C.J. Macgregor, J.H. Williams, J.R. Bell and C.D. Thomas (2019) Moth biomass increases and declines over 50 years in Britain. Nature Ecology & Evolution, 3, 1645–1649.

C.J. Macgregor, C.D. Thomas, D.B. Roy, M.A. Beaumont, J.R. Bell, T. Brereton, J.R. Bridle, C. Dytham, R. Fox, K. Gotthard, A.A. Hoffmann, G. Martin, I. Middlebrook, S. Nylin, P.J. Platts, R. Rasteiro, I.J. Saccheri, R. Villoutreix, C.W. Wheat and J.K. Hill (2019) Climate-induced phenology shifts enable range expansions in species with multiple reproductive cycles per year. Nature Communications, 10, 4455.

L.R. Harper, L. Lawson Handley, A.I. Carpenter, M. Ghazali, C. Di Muri, C.J. Macgregor, T.W. Logan, A. Law, T. Breithaupt, D.S. Read, A. McDevitt and B. Hänfling (2019) Environmental DNA (eDNA) metabarcoding of pond water as a tool to survey conservation and management priority mammals in the UK. Biological Conservation, 238, 108225.

P. Banza, C.J. Macgregor*, A.D.F. Belo, R. Fox, M.J.O. Pocock and D.M. Evans (2019) Wildfire alters the structure and seasonal dynamics of Mediterranean nocturnal pollination networks. Functional Ecology, 33, 1882–1892. *corresponding author

C.J. Macgregor, M.J.O. Pocock, R. Fox and D.M. Evans (2019) Street lights influence the success and quality of pollination in a nocturnally-pollinated plant. Ecosphere, 10, e02550.

C.J. Macgregor, J.J.N. Kitson, R. Fox, C. Hahn, D.H. Lunt, M.J.O. Pocock and D.M. Evans (2019) Construction, validation and application of nocturnal pollination networks in an agroecosystem, using light microscopy and DNA metabarcoding. Ecological Entomology, 44, 17–29.

C.J. Macgregor, D.J. Hoare, M.S. Parsons and O.T. Lewis (2017) Interspecific competition and host-plant patch qualities affect the distribution and abundance of a rare British moth, Cucullia lychnitis. Journal of Insect Conservation, 21, 137–146.

C.J. Macgregor, D.M. Evans, R. Fox and M.J.O. Pocock (2016) The dark side of street lighting: impacts on moths and evidence for the disruption of nocturnal pollen transport. Global Change Biology, 23, 697–707.

C.J. Macgregor, M.J.O. Pocock, R. Fox and D.M. Evans (2015) Pollination by nocturnal Lepidoptera, and the effects of light pollution: a review. Ecological Entomology, 40, 187–198.