Thiemann, Gregory W
Undergraduate Program Director
, Dalhousie University
MSc , Dalhousie University
BSc (Honours) , McMaster University
My research focuses on the foraging ecology and conservation of Arctic carnivores. By examining the trophic relationships between top predators and their prey, we can define the structure of food webs and monitor changes in ecosystems over time. By understanding where, when, and how predators hunt for food, we can better act to protect wildlife populations and entire ecosystems.
Much of my research has involved the use of fatty acid signature analysis to examine the diets of marine and terrestrial carnivores. This technique is based on the knowledge that ingested dietary fatty acids (such as “omega-3’s”) are predictably incorporated into a predator’s fat stores. Therefore, the fatty acid profile of an animal can be used to make inferences about its foraging habits.
Long-term climate warming is having rapid and widespread effects on northern ecosystems. This in turn is altering the relationships between northern aboriginal communities and the wildlife populations they utilize. Accurate information on the current structure and functioning of food webs will help us predict how wildlife populations will change in the future and how these changes will impact the lives of people in the North. FES is uniquely positioned to examine the complex ecological, social, and economic changes that will result from a warming Arctic environment.
- Characterizing the Denning Habitat and Movements of Polar Bears in Southern Hudson Bay
- Community-Based Monitoring of Polar Bear Foraging in Nunavut
- Foraging Habits and Contaminant Burdens of High Arctic Ringed Seals
- Nutritional Physiology of Bears Under Human Care
- NSERC Postdoctoral Fellowship
- Killam Postdoctoral Fellowship
- Alberta Ingenuity Postdoctoral Prize
- Postdoctoral Research Award - University of Alberta Celebration of Research & Innovation
Galicia, M.P., G.W. Thiemann, and M.G. Dyck. 2020. Correlates of seasonal change in the body condition of an Arctic top predator. Global Change Biology 26: 840–850. https://doi.org/10.1111/gcb.14817
Shave, J.R., A.E. Derocher, S.G. Cherry, and G.W. Thiemann. 2019. Chronic stress and body condition of wolf-killed prey in Prince Albert National Park, Saskatchewan. Conservation Physiology 7(1): coz037. https://doi.org/10.1093/conphys/coz037
Brown, T.A., M.P. Galicia, G.W. Thiemann, S.T. Belt, D.J. Yurkowski, M.G. Dyck. 2018. High contributions of sea ice derived carbon in polar bear (Ursus maritimus) tissue. PLoS ONE 13(1): e0191631. https://doi.org/10.1371/journal.pone.0191631
Laforest, B.J., J. Hebert, M.E. Obbard, G.W. Thiemann. 2018. Traditional Ecological Knowledge of polar bears in the northern Eeyou Marine Region, Québec, Canada. Arctic 71: 40-58.
Sciullo, L., G.W. Thiemann, N.J. Lunn, S.H. Ferguson. 2017. Intraspecific and temporal variability in the diet composition of female polar bears in a seasonal sea ice regime. Arctic Science 3: 672–688. https://www.nrcresearchpress.com/doi/pdf/10.1139/as-2017-0004
Bromaghin, J.F., S.M. Budge, G.W. Thiemann and K.D. Rode. 2017. Simultaneous estimation of diet composition and calibration coefficients with fatty acid signature data. Ecology and Evolution 7: 6103-6113. https://doi.org/10.1002/ece3.3179
Regehr, E.V., K.L. Laidre, H. Resit Akçakaya, S.C. Amstrup, T.C. Atwood, N.J. Lunn, M. Obbard, H. Stern, G.W. Thiemann, and Ø. Wiig. 2016. Conservation status of polar bears (Ursus maritimus) in relation to projected sea-ice declines. Biology Letters 12: 20160556. https://doi.org/10.1098/rsbl.2016.0556
Sciullo, L., G.W. Thiemann and N.J. Lunn. 2016. Comparative assessment of metrics for monitoring the body condition of polar bears in Western Hudson Bay. Journal of Zoology, London 300: 45-58. https://doi.org/10.1111/jzo.12354
Galicia, M.P., G.W. Thiemann, M.G. Dyck, S.H. Ferguson and J.W. Higdon. 2016. Dietary habits of polar bears in Foxe Basin, Canada: possible evidence of a trophic regime shift mediated by a new top predator. Ecology and Evolution 16: 6005-6018. https://doi.org/10.1002/ece3.2173
Galicia, M.P., G.W. Thiemann, M.G. Dyck, and S.H. Ferguson. 2015. Characterization of polar bear (Ursus maritimus) diets in the Canadian High Arctic. Polar Biology 38: 1983-1992. https://doi.org/10.1007/s00300-015-1757-1