Shoals and schools: back to the heuristic definitions and quantitative references

  title={Shoals and schools: back to the heuristic definitions and quantitative references},
  author={Johann Delcourt and Pascal Poncin},
  journal={Reviews in Fish Biology and Fisheries},
The terms ‘shoal’, ‘swarm’ and ‘school’ are very frequently used in research on collective behaviours in animals. Pitcher’s definitions are accepted as the authority in the field but are based on a conceptual criterion of sociability. Without call into question the basis of these definitions, they do not provide tools to determine these behaviours quantitatively. To compare studies between populations, species, taxa or different experimental treatments, and between different authors… 
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