Mar Biodiv DOI 10.1007/s12526-014-0215-6 OCEANARIUM Cooperative hunting and gregarious behaviour in the zebra lionfish, Dendrochirus zebra J. R. Rizzari & O. M. Lönnstedt Received: 17 October 2013 /Revised: 11 February 2014 /Accepted: 12 February 2014 # Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg 2014 Cooperative hunting is considered one of the most ubiquitous (Albins and Lyons 2012), and is likely an idiosyncratic trait of forms of cooperative behaviour in animals, and has been exten- lionfishes. Contrary to earlier suggestions that D. zebra is a sively studied in a range of taxa, including birds, mammals, fish and insects (Packer and Ruttan 1988). The zebra lionfish, Dendrochirus zebra (Cuvier 1829), feeds on small crustaceans and fishes and has been previously described as a solitary predator in which individuals hunt exclusively by themselves (Moyer and Zaiser 1981). Here, we report the occurrence of cooperative hunting in D. zebra from coral reefs around Lizard Island, northern Great Barrier Reef, Australia (14°40′S, 145°28′ E). During September–December 2012, three different pairings (2–3 individuals) of D. zebra were observed cooperatively hunting in the field, therefore offering insight into a thus far unknown social behaviour in this species (Moyer and Zaiser 1981). Furthermore, hunting behaviour was filmed with video cameras (GoPro, Woodman Labs; see supplementary material) in a laboratory setting. As in the field (Fig. 1a), D. zebra pairs were observed hunting together on six different occasions in groups of 2–3 individuals. In each case, individuals would swim towards prey (cardinalfishes, Apogon doerderlini) undulating their dorsal spines, using their web-like fins as a visual-barrier, together herding prey into a confined area. Individuals would then take turns striking at their prey (Fig. 1b). On several occasions, one individual would proceed to produce a jet of water directed towards the prey (believed to confuse/distract prey increasing the chance of a successful predatory event; Albins and Lyons 2012). This mode of hunting has been documented for the invasive red lionfish, Pterois volitans Electronic supplementary material The online version of this article (doi:10.1007/s12526-014-0215-6) contains supplementary material, which is available to authorized users. J. R. Rizzari (*) : O. M. Lönnstedt ARC Centre of Excellence for Coral Reef Studies and School of Marine and Tropical Biology, James Cook University, Townsville, QLD 4811, Australia Fig. 1 Lionfish (Dendrochirus zebra) observed a hunting together, b e-mail: [email protected] pectoral fins flared out herding prey and c living together Mar Biodiv social recluse (Moyer and Zaiser 1981), the current findings References suggest that D. zebra exhibits gregarious behaviour, living together in groups of 3 (Fig. 1c). To our knowledge, this is the Albins MA, Lyons PJ (2012) Invasive red lionfish Pterois volitans first documented case of intraspecific cooperative hunting and blow directed jets of water at prey fish. Mar Ecol Prog Ser gregarious behaviour in lionfish. Recent findings (Lönnstedt 448:1–5 and McCormick 2013) suggest that this hunting behavior is Lönnstedt OM, McCormick MI (2013) Ultimate predators: lionfish have evolved to circumvent prey risk assessment abilities. PLoS ONE 8: mirrored by P.volitans, which could have implications for e75781 hunting effectiveness of invasive lionfish in the Caribbean. Moyer JT, Zaiser MJ (1981) Social organization and spawning behavior of the Pteroine Fish Dendrochirus zebra at Miyake-jima, Japan. Jpn J Ichthyol 28:52–69 Acknowledgment We thank Lizard Island Research Station for logis- Packer C, Ruttan L (1988) The evolution of cooperative hunting. Am Nat tical support. 132:159–198.