I am a conservation biologist who integrates the fields of behavior, physiology, and ecology.
My primary research interests lie in examining the underlying mechanisms for how individuals interact with their environments, with a particular focus on avian systems. Revealing such mechanisms is critical to effective management and conservation. I employ a wide range of techniques when addressing these types of questions, including: observational field studies, wild and captive experiments, hormone analysis, and stable isotope ecology. My goals are to: 1) provide detailed information on ecological and physiological mechanisms that can reveal processes shaping behavior, life history, and demographics throughout an organism’s life-cycle and, 2) determine how anthropogenic disturbances influence these processes.
From hourly to annual time scales, individuals are faced with innumerable decisions that ultimately shape their fitness. These include: habitat selection, foraging strategy, predator avoidance, phenology, and conspecific interaction. These decisions have wide ranging effects on survival and reproductive success. Thus, the processes that determine how, when, and where individuals complete life-cycle events shape their capacity, and ultimately the capacity of the population, to respond to environmental change. I study how the physiology and behavior of individuals is shaped by their environment throughout their full life-cycles. My previous and ongoing research in this area spans local and international scales and involves collaborations with numerous organizations.
Research webpage: www.christophertonra.com/research.html
ENR 3300 – Introduction to Forestry Fisheries and Wildlife
ENR 5364.02 – Avian Biology and Management
Prospective Graduate Students
If you are interested in joining my lab, please send me an email with 1) your research interests, 2) a current CV, 3) your GPA and GRE scores, and 4) a list of references.
Reprints are available through: www.christophertonra.com/publications.html
Skinner, A.A.*, M.P. Ward, I. Souza-Cole, J.R. Wright*, F.R. Thompson III, T.J. Benson, S.N. Matthews, C.M. Tonra. 2022. High spatiotemporal overlap in the non-breeding season despite variable breeding latitudes in the Eastern Whip-poor-will (Antrostomus vociferus). Diversity and Distributions 28: 712-726.
Brunner, A.R.*, P.P. Marra, and C.M. Tonra. 2022. Vulnerable Neotropical migratory songbird demonstrates flexibility in space use in response to rainfall change. Ornithology 139: ukac005.
Wright, J.R.*, S.N. Matthews, C.C. Pinchot, and C.M. Tonra. 2022. Preferences of avian seed-hoarders in advance of potential American chestnut reintroduction. Forest Ecology and Management 511: 120133.
Tonra, C.M., M. Hallworth, T. Boves, J. Reese, L. Bulluck, M. Johnson, C. Viverette, K. Percy, E.A. Ames*, A. Matthews, M.C. Slevin, R. R. Wilson, and E.I. Johnson. 2019. Concentration of a widespread breeding population in few critically important nonbreeding areas: Migratory connectivity in Prothonotary Warbler. Condor: Ornithological Applications 121: duz019.
Tonra, C.M. and M.W. Reudink. 2018. Expanding the traditional definition of molt-migration. Auk: Ornithological Advances 135:1123-1132.
Marra, Peter P., Emily B. Cohen, Scott R. Loss, Jordan E. Rutter and Christopher M. Tonra. 2015. A call for full annual cycle research in animal ecology. Biology Letters 11:20150522
Tonra, Christopher M., Christiaan Both and Peter P. Marra. 2015. Incorporating site and year-specific deuterium ratios (δ2H) from precipitation into geographic assignments of a migratory bird. Journal of Avian Biology 46(3): 266-274.
Tonra, C.M., K.L.D. Marini, P.P.Marra, R.R. Germain, R.L. Holberton, and M.W. Reudink. 2014. Color expression in experimentally regrown feathers of an overwintering migratory bird: implications for signaling and seasonal interactions. Ecology and Evolution 4: 1222-1232.
Tonra, C.M., P.P. Marra, and R.L. Holberton. 2013. Experimental and observational studies of seasonal interactions between overlapping life history stages in a migratory bird. Hormones and Behavior 64: 825–832.
Croston, R., C.M. Tonra, S.K. Heath, and M.E. Hauber. 2012. Flange color differences in brood parasitic Brown-headed Cowbirds from nests of two host species. Wilson Journal of Ornithology 124: 139-145.
Tonra, C.M., P.P. Marra, and R.L. Holberton. 2011. Early elevation of testosterone advances migratory preparation in a songbird. Journal of Experimental Biology 214: 2761-2767.
Tonra, C.M., P.P. Marra, and R.L. Holberton. 2011. Migration phenology and winter habitat quality are related to circulating androgen in a long-distance migratory bird. Journal of Avian Biology 42: 397-404.
Angelier F., C.M. Tonra, R.L. Holberton, and P.P. Marra. 2011. Short-term changes in body condition in relation to habitat and climate in American redstarts during the non-breeding season. Journal of Avian Biology 42: 355-341.
Angelier F., C.M. Tonra, R.L. Holberton, and P.P. Marra. 2010. How to capture wild passerine species to study baseline corticosterone levels. Journal of Ornithology 151: 415-422.
Tonra, C.M., M.D. Johnson, M.E. Hauber, and S.K. Heath. 2009. Does nesting habitat influence hatching synchrony between brood parasitic brown-headed cowbirds (Molothrus ater) and two hosts? Ecography 32: 497-503.
Tonra, C.M., M.E. Hauber, S.K. Heath, and M.D. Johnson. 2008. Ecological correlates and sex differences in early development of a generalist brood parasite. Auk 125: 205-213.