With a Little Help from My Friends: Group Orientation by Larvae of a Coral Reef Fish

PLoS One. 2015 Dec 1;10(12):e0144060. doi: 10.1371/journal.pone.0144060. eCollection 2015.

Abstract

Theory and some empirical evidence suggest that groups of animals orient better than isolated individuals. We present the first test of this hypothesis for pelagic marine larvae, at the stage of settlement, when orientation is critical to find a habitat. We compare the in situ behaviour of individuals and groups of 10-12 Chromis atripectoralis (reef fish of the family Pomacentridae), off Lizard Island, Great Barrier Reef. Larvae are observed by divers or with a drifting image recording device. With both methods, groups orient cardinally while isolated individuals do not display significant orientation. Groups also swim on a 15% straighter course (i.e. are better at keeping a bearing) and 7% faster than individuals. A body of observations collected in this study suggest that enhanced group orientation emerges from simple group dynamics rather than from the presence of more skilful leaders.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Behavior, Animal / physiology*
  • Coral Reefs
  • Fishes / physiology*
  • Larva / physiology*
  • Orientation / physiology*
  • Perciformes / physiology*
  • Swimming / physiology

Grants and funding

The authors are grateful for The Hermon Slade Foundation (http://www.hermonslade.org.au) grant to JML and CBP, ARC (http://www.coralcoe.org.au) Discovery Grant DP110100695 to JML, CBP and U.E.Siebeck, NSF (http://www.nsf.gov) OTIC-1155698 and RSMAS (http://www.rsmas.miami.edu) Startup grant to CBP. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.