I am a postdoctoral researcher at the Department of Wildlife, Fish and Environmental Studies at SLU, Umeå. My research focuses on using novel methods to improve the downstream migration of brown trout and Atlantic salmon in regulated rivers. Until recently, research efforts have been dedicated to enhancing the upstream migration of fish past hydropower dams. Less attention has been given to post-spawning fish that are migrating back downstream.
Some salmon and trout spawn more than once in their life. These fish, known as repeat spawners, will complete the long migration between feeding and spawning habitats multiple times. Research suggests that repeat spawners may contribute significantly to juvenile productivity. I am looking into repeat spawning prevalence in different populations of trout and salmon and how this could influence efforts to protect repeat spawners from the negative impacts of hydropower.
My PhD focused on fish behaviour and welfare in aquaculture. I assessed whether fish behaviour and their capacity to learn could be used to improve fish welfare and sustainability at fish farms. I also tested Atlantic salmon buoyancy limits and the consequences this has for salmon lice management. Before my PhD, my honours thesis focused on juvenile fish ecology in seagrass, mangrove and mudflat habitats in South Australia.
I am passionate about aquatic wildlife and have broad interests in ecology and applied topics. I am particularly interested in fish behaviour and exploring ways to mitigate human impacts on our aquatic ecosystems.
I graduated from the University of Adelaide, Australia, in 2016 with Honours in Ecology and Environmental Sciences. In 2018, I started my PhD in Sustainable Aquaculture and Marine Ecology at the University of Melbourne, working with the Norwegian Institute of Marine Research. I finished my PhD in 2021 and began working as an Aquatic Animal Health and Environmental Assessment officer for the Aquaculture division of the South Australian government. In January 2023, I started my postdoc at SLU Wildlife, Fish and Environmental Studies in Umeå.
G. Macaulay, L. T. Barrett and T. Dempster (2022) Recognising trade-offs between welfare and environmental outcomes in aquaculture will enable good decisions. Aquaculture Environment Interactions, Vol. 14 Pages 219-227
O Folkedal, G Macaulay, JE Fosseidengen, G Mikkelsen, J Myrland, B Søvegjarto, TO Klepaker, A Fernö, T Dempster, F Oppedal, LH Stien (2022) Deployment of hydroacoustic feeding control in salmon sea-cages; biological and technical considerations. Aquaculture, Vol. 561 Pages 738700
P. McIntosh, L. T. Barrett, F. Warren-Myers, A. Coates, G. Macaulay, A. Szetey, N Robinson, C White, F Samsing, F Oppedal, O Folkedal, P Klebert, T Dempster (2022). Supersizing salmon farms in the coastal zone: A global analysis of changes in farm technology and location from 2005 to 2020. Aquaculture, Vol. 553 Pages 738046
M. Sievers, O. Korsoen, F. Warren-Myers, F. Oppedal, G. Macaulay, O. Folkedal and T. Dempster (2022) Submerged cage aquaculture of marine fish: A review of the biological challenges and opportunities. Reviews in Aquaculture, Vol. 14 Issue 1 Pages 106-119
T. Oldham, G. Macaulay, M. Stalheim and F. Oppedal (2021) Operculum PIT tagging: a viable alternative to avoid human consumption in processed salmon. Animal Biotelemetry, Vol. 9 Issue 1
G. Macaulay, F. Warren-Myers, L. T. Barrett, F. Oppedal, M. Føre, and T. Dempster (2021) Tag use to monitor fish behaviour in aquaculture: a review of benefits, problems and solutions. Reviews in Aquaculture, Vol. 13 Issue 3 Pages 1565-1582
G. Macaulay, S. Bui, F. Oppedal and T. Dempster (2021) Challenges and benefits of applying fish behaviour to improve production and welfare in industrial aquaculture. Reviews in Aquaculture, Vol. 13 Issue 2 Pages 934-948
G. Macaulay, S. Bui, F. Oppedal and T. Dempster (2020) Acclimating salmon as juveniles prepares them for a farmed life in sea-cages. Aquaculture, Vol. 523 Pages 735227
G. Macaulay, D. Wright, F. Oppedal and T. Dempster (2020) Buoyancy matters: Establishing the maximum neutral buoyancy depth of Atlantic salmon. Aquaculture, Vol. 519 Pages 734925