Safety in numbers: shoal size choice by minnows under predatory threat

@article{Hager2004SafetyIN,
  title={Safety in numbers: shoal size choice by minnows under predatory threat},
  author={Mary Catherine Hager and Gene S. Helfman},
  journal={Behavioral Ecology and Sociobiology},
  year={2004},
  volume={29},
  pages={271-276}
}
SummaryLarger animal groups often provide greater protection from predators. An individual might therefore be expected to join the larger of two groups. To test this, we hypothesized that fathead minnows would choose to associate with the larger of two shoals and that the presence of a predatory largemouth bass would influence their shoal size choice. Individual minnows were presented with a series of choices between two shoal sizes, ranging from 1 to 28 fish, both with and without a predator… 
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