Putative Male – Male Agonistic Behaviour in Free-Living Zebra Sharks, Stegostoma fasciatum

Juerg M. Brunnschweiler 1, *, Harold L. Pratt, Jr. 2
1 Swiss Federal Institute of Technology
2 Center for Shark Research, Mote Marine Laboratory

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 384
Abstract HTML Views: 488
PDF Downloads: 0
Total Views/Downloads: 872
Unique Statistics:

Full-Text HTML Views: 241
Abstract HTML Views: 298
PDF Downloads: 0
Total Views/Downloads: 539

© 2008 Brunnschweiler and Pratt

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Swiss Federal Institute of Technology, Euresearch Zurich, Careum, Moussonstrasse 2, CH-8044 Zurich, Switzerland; Tel: +41-44-6345355; Fax: +41-44-6345351; E-mail:


Abstract: We analysed digital still photographs of two interacting free-living male zebra sharks. The recorded behaviours are similar in appearance to some male – female courtship and mating patterns in elasmobranchs and several of the positions are similar to or resemble reproductive behaviours known from other species. We discuss two possible hypotheses that may explain the interaction, sexual behaviour and an agonistic behaviour. We reject the same-sex hypothesis and propose that the event was of agonistic nature.

Keywords: Agonistic behaviour, Elasmobranch, Homosexual, Male-male mating, Mating behaviour, Pectoral bite, Shark, Sexual behaviour, Stegostoma fasciatum, Zebra shark.