Abstract
The goal of this work was to determine how the foraging behaviour of Akodon azarae changes with predation risk and food availability in cropfield borders of Buenos Aires, Argentina. Our hypotheses were that A. azarae has a greater foraging efficiency in safe areas than in risky ones and that the foraging behaviour of A. azarae also depends on the level of resources. We measured giving-up densities (GUDs) and food consumption twice a year in artificial foraging patches (bottles with known amounts of millet seed) in covered and open areas and with two different levels of seed abundance. In both periods, GUDs were lower in the covered areas than in the open ones independently of food level. Consumption increased with food level in covered areas but not in open areas. Based on these results, we conclude that A. azarae appears to maximize its consumption depending on predation risk.
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Acknowledgments
We thank Gerardo Cueto and Beatriz Gonzalez for their statistical advice and Joel S. Brown for his useful comments on early versions of this manuscript. We also thank D. Gaynor people for their assistance during field work. We greatly acknowledge commentaries on a previous version of the manuscript by R. Cavia, M.S. Fernández, I.E. Gómez Villafañe, D. Bilenca and V. León. This work was funded by University of Buenos Aires and CONICET grants.
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Fraschina, J., Knight, C. & Busch, M. Foraging efficiency of Akodon azarae under different plant cover and resource levels. J Ethol 27, 447–452 (2009). https://doi.org/10.1007/s10164-008-0140-x
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DOI: https://doi.org/10.1007/s10164-008-0140-x