Local interactions and global properties of wild, free-ranging stickleback shoals

Ward, Ashley J. W.; Schaerf, Timothy M.; Herbert-Read, James E.; Morrell, Lesley; Sumpter, David J. T.; Webster, Mike M.

Abstract

Collective motion describes the global properties of moving groups of animals and the self-organized, coordinated patterns of individual behaviour that produce them. We examined the group-level patterns and local interactions between individuals in wild, free-ranging shoals of three-spine sticklebacks, Gasterosteus aculeatus. Our data reveal that the highest frequencies of near-neighbour encounters occur at between one and two body lengths from a focal fish, with the peak frequency alongside a focal individual. Fish also show the highest alignment with these laterally placed individuals, and generally with animals in front of themselves. Furthermore, fish are more closely matched in size, speed and orientation to their near neighbours than to more distant neighbours, indicating local organization within groups. Among the group level properties reported here, we find that polarization is strongly influenced by group speed, but also the variation in speed among individuals and the nearest neighbour distances of group members. While we find no relationship between group order and group size, we do find that larger groups tend to have lower nearest neighbour distances, which in turn may be important in maintaining group order.

Citation

Ward, A. J. W., Schaerf, T. M., Herbert-Read, J. E., Morrell, L., Sumpter, D. J. T., & Webster, M. M. (2017). Local interactions and global properties of wild, free-ranging stickleback shoals. Royal Society Open Science, 4(7), 170043. https://doi.org/10.1098/rsos.170043

• Journal Article Type: Article
• Acceptance Date: Jun 7, 2017
• Online Publication Date: Jul 12, 2017
• Publication Date: Jul 12, 2017
• Deposit Date: Jul 13, 2017
• Publicly Available Date: Jul 13, 2017
• Journal: Royal Society open science
• Electronic ISSN: 2054-5703
• Publisher: The Royal Society
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: 7
• Article Number: ARTN 170043
• Pages: 170043
• DOI: https://doi.org/10.1098/rsos.170043
• Keywords: Collective behaviour, Schooling, Grouping
• Public URL: https://hull-repository.worktribe.com/output/453569
• Publisher URL: http://rsos.royalsocietypublishing.org/content/4/7/170043
• Additional Information: This is a copy of an open access article published in Royal Society open science, 2017, v.4.