Dr. John M. Fryxell
Professor & Chair
Department of Integrative Biology
Office: SSC 2461
Lab: SSC 2405/2406
B.Sc. - Britsh Columbia 1977
Ph.D. - British Columbia 1985
My research focuses on interactions between behavior and consumer-resource dynamics. A mix of theoretical and empirical approaches is used to consider the dynamics of specific systems. Theoretical questions of interest include herbivore and carnivore movement in relation to resource availability and predation risk, optimal diet, patch selection, and dispersal patterns in heterogeneous environments, the effect of social interference and territoriality on consumer-resource interactions, and impacts of harvesting by humans on fish and mammal populations.
Empirical work has been concentrated on 3 different terrestrial ecosystems over the past decade: large herbivores and carnivores in Serengeti National Park (Tanzania), woodland caribou, wolves, and moose in boreal forests of northern Ontario (Canada), and mustelid carnivores and other small mammals in boreal forests of northern Ontario. In each case, my graduate students and I conduct detailed field and experimental studies of behavioral ecology of both predators and prey. Theoretical models are then used to assess the implications of behavioral strategies on population and community dynamics and model predictions are then tested against long-term observational data from terrestrial ecosystems.
Kevin McCann and I recently initiated a collaborative research program on spatial food web dynamics of phytoplankton and zooplankton populations in massive aquatic mesocosms in the new Limnotron facility at the Biodiversity Institute of Ontario. Initial experiments relate to resource- vs predator- and ratio-dependent functional and numerical responses, responses of predator and algal populations to pulsed versus continuous nutrient influx, resource- and density-dependent diffusion patterns by zooplankton and phytoplankton, and spatial pattern formation in relation to population fluctuations.
An ongoing applied research interest relates to sustainable harvesting of fish and mammal populations. Key questions relate to long-term stability of harvested populations due to dynamic variation in harvester effort, effects of bioeconomic dynamics on long-term stability of fish stocks and prices, and spatial processes in harvested populations with and without no-harvest reserves.
Holdo, R. M., Fryxell, J. M., Sinclair, A.R.E., Dobson, A., Holt, R. D. (2011), Predicted Impact of Barriers to Migration on the Serengeti Wildebeest Population. PLoS ONE 6(1): e16370. doi:10.1371/journal.pone.0016370.
Dalziel, B.D., Morales, J.M., Fryxell, J.M., Fitting Dynamic Models to Animal Movement Data: The Importance of Probes for Model Selection, a Replay to Franz and Caillaud. The American Naturalist,Vol. 175, 6, June 2010
Sinclair, A.R.E., Metzger, K., Brashares, J.S., Nkwabi, A., Sharam, G., Fryxell, J.M., Trophic Cascades in African Savanna: Serengeti as a Case Study, Tropic Cascades (Terborgh et all, eds), Island Press, pages 255-274, (2010).
Yott, A., Rosatte, R. Schaefer, J.A., Hamr,J., Fryxell, J.M., Movement and Spread of a Founding Population of Reintroduced Elk, (Cervus elaphus) in Ontario, Canada, Society for Ecological Restorartion International, doi: 10.1111/j.1526-100X.2009.00639.x
Holdo, Ricardo M., Holt, Robert D., Fryxell, John M. Opposing Rainfall and Plant Nutritional Gradients Best Explain the Wildebeest Migration in the Serengeti. The American Naturalist, Vol. 173 (4), April 2009.
Dalziel, B.D., Morales, J.M., & Fryxell, J.M. (2008). Fitting Probability Distributions to Animal Movement Trajectories: Using Artificial Neural Networks to Link Distance, Resources, and Memory. The American Naturalist, Vol. 172, No.2., pp.248-258.
Haydon, D.T., Morales, J.M., Yott, A., Jenkins, D.A., Rosatte, R. & Fryxell, J.M. (2008). Socially informed random walks: incorporating group dynamics into models of population spread and growth. Proc. R. Soc. B 275, pp: 1101-1109.
Thompson, I.D., Maher, S.C., Rouillard, D.P., Fryxell, J.M., Baker, J.A. (2007). Accuracy of forest inventory mapping: Some Implcations for boreal forest management. Forest Ecology and Management 252, pp 208-221.
A.R.E. Sinclair, S.A.R. Mduma, J.G.C. Hopcraft, J.M. Fryxell,R. Hilborn, and S. Thirgood. (2007). Long-Term Ecosystem Dynamics in the Serengeti: Lessons for Conservation. Conservation Biology Volume 21, No. 3, 580–590.
Thirgood, S.J., A. Mosser, S. Tham, J.G.C. Hopcraft, E. Mwangomo, T. Mlengeya, M. Kilewo, J.M. Fryxell, A.R.E. Sinclair, and M. Borner. 2004. Can parks protect migratory ungulates? The case of the Serengeti-Mara wildebeest. Animal Conservation 7: 113–120.
Boyce, M.S., J.S. Mao, E.H. Merrill, D. Fortin, M.G. Turner, J. Fryxell, and P. Turchin. 2003. Scale and hetergeneity in habitat selection by elk in Yellowstone National Park. Ecoscience 10(4):421-431.
Fortin, D., J.M. Fryxell, L. O’Brodovich, and D. Frandsen. 2003. Foraging ecology of bison at the landscape and plant community levels: the applicability of energy maximization principles. Oecologia 134:219-227.
Fryxell, J.M., C. Bergman, D. Fortin, and J. Wilmshurst. 2001. On the scale dependence of foraging in terrestrial herbivores. Pages 271-275 in Proceedings of XIX International Grasslands Congress (Gomide, J.A., W. Mattos, and S.C. da Silva, eds), FEALQ, Sao Pedro, Brazil, 1097 pp.
Sinclair, A.R.E., C.J. Krebs, J.M. Fryxell, R. Turkington, S. Boutin, R. Boonstra, P. Seccombe Hett, P. Lundberg, and L. Oksanen. 2000. Testing hypotheses of trophic level interactions: a boreal forest ecosystem. Oikos 89:313-328.
BIOL*3110 Population Ecology
BIOL*4150 Wildlife Conservation and Management
ZOO*4410 Field Ecology
Derek Morningstar (MSc)
Post Doctoral Fellows
Dr. Tal Avgar
Dr. Gustavo Betini