Research Interests

My research explores the influence of energy supply and demand on animal behavior. Energy flow through organisms has long been recognized as a central process underlying ecological interactions and evolutionary adaptation. More recently, behavioral energetics, which examines how behavior affects and is affected by energy flow through an organism, has become an important theme in behavioral ecology. The rate and amount of net energy acquisition and storage are clearly linked to production, therefore it is reasonable to propose energetic 'costs' and physiological limits as selective forces affecting the expression of behavioral strategies. To investigate the influence of energy intake, storage, and expenditure on animal decision making I combine experimental field studies of behavior with in vivo estimates of body composition and energy expenditure. My past and current research examines aspects of foraging decisions and mating tactics in birds and mammals. Presently, research in my lab is focusing on various aspects of the reproductive behavior and energetics of male ground squirrels.

Recent Publications

• Bachman GC. 2000. Changes in leukocyte counts in hibernators from spring through summer. AMERICAN ZOOLOGIST 40 (6): 933-933.
• Bachman, G., F. Widemo. 1999. Relationships between body composition, body size, and alternative reproductive tactics in a lekking sandpiper, the Ruff (Philomachus pugnax). Functional Ecology: 13:411-416.
• Bachman, G.C., Chappell, M.A. 1998. Energetic cost of begging in house wrens (Troglodytes aedon). Animal Behaviour 55:1607-1618.
• Chappell MA, Bachman GC.1998. Exercise capacity of House Wren nestlings: Begging chicks are not working as hard as they can. AUK 115 (4): 863-870.
• Chappell, M. A., Bachman, G. C. and Hammond, K. A.1997. The heat increment of feeding in house wren chicks: Magnitude, duration, and substitution for thermostatic costs. Journal of Comparative Physiology B 167: 313-318.
• Bachman, G.C. and S.L. Vehrencamp. 1995. "Ecological Energetics of Terrestrial Vertebrates" , p. 549-565 in "Encyclopedia of Environmental Biology", Academic Press.
• Bachman, G.C. 1994. Food restriction effects on the body composition of free-living ground squirrels. Physiological Zoology 67:756-770.
• Bachman, G.C. 1993. The effect of body condition on the trade-off between vigilance and foraging in Belding's ground squirrels. Animal Behaviour 46:233-244.