Effects of Food Availability on Space and Refuge Use by a Neotropical Scatterhoarding Rodent

Authors

  • Willem-Jan Emsens,

    Corresponding author
    1. Centre for Ecosystem Studies, Wageningen University, Wageningen, The Netherlands
    2. Ecosystem Management Research Group, Department of Biology, University of Antwerp, Antwerp, Belgium
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  • Lennart Suselbeek,

    1. Centre for Ecosystem Studies, Wageningen University, Wageningen, The Netherlands
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  • Ben T. Hirsch,

    1. School of Environment & Natural Resources, Ohio State University, Columbus, Ohio, U.S.A
    2. Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
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  • Roland Kays,

    1. Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
    2. Nature Research Center, North Carolina Museum of Natural Sciences, Raleigh, North Carolina, U.S.A
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  • Annemarie J. S. Winkelhagen,

    1. Centre for Ecosystem Studies, Wageningen University, Wageningen, The Netherlands
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  • Patrick A. Jansen

    1. Centre for Ecosystem Studies, Wageningen University, Wageningen, The Netherlands
    2. Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
    3. Centre for Ecological and Evolutionary Studies, University of Groningen, Groningen, The Netherlands
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Abstract

Animals that rely on refuges for safety can theoretically increase their foraging area without simultaneously increasing predation risk and travel costs by using more refuges. The key prediction of this theory, a negative correlation between food abundance, home range size and the number of refuges used, has never been empirically tested. We determined how home range size and refuge use by the Central American agouti (Dasyprocta punctata) varied across a gradient of abundance of the agoutis' principal food source: seeds and fruits of the palm Astrocaryum standleyanum. We used both manual and automated radio telemetry to measure space use of 11 agoutis during 2 mo of the Astrocaryum fruiting season, and of another set of 10 agoutis during 6 mo in which the animals largely relied on cached Astrocaryum seeds. We found that agoutis living in areas of lower food density had larger home ranges, and that all individuals used multiple refuges. The number of refuges, however, was not correlated with home range size. Consequently, agoutis that had larger home ranges roamed farther from their refuges. These results suggest that agoutis increase their home range size in response to food scarcity at the cost of their safety.

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