Increase of individual Prey Capture Rate based on Cooperation between the Peppered Moray (Muraenidae) and the Lyretail Grouper (Serranidae) in the Gulf of Aqaba/Red Sea - Diplomarbeit - Victoria von Mach

Abstract

The study deals with cooperation between members of different species in order to increase their individual capture rate. In the last years cooperation on an interspecific level reached attention relating to overcome the problems of intraspecific coordinated hunting. The adoption of different roles during a joint hunt which facilitate a successful association is a lot easier for individuals of different species. The study examines the association of the peppered moray (Gymnothorax griseus) and the lyretail grouper (Variola louti) in the Gulf of Aqaba. It is a comparison to Bsharys et al. (2006) investigations of the giant moray (G. javanicus) and the coral grouper (Plectropomus pessuliferus). The survey reveals that the species act in the same highly coordinated manner including communication like giant moray and coral grouper. The species stayed three times longer in contact than expected and during these contacts four signals of the lyretail grouper with different meanings could be recorded. Furthermore, groupers have a higher capture rate in cooperation with a moray (4.08 h-1) compared to hunting solitary (1.78 h-1). There are also impressive indications that these nocturnal morays benefit in the same manner from these associations. The willingness for cooperation increases with both proceeding daytime and ascending hunger level. Since the prey of the two predators is too small to be divided, monopolization of the carcass and rivalry can´t emerges. In addition indication that cooperation depends on groupers size is given in this study and so it seems that these coordinated hunts are about a learned behavior. The study documents for the first time that V. louti communicates additionally with octopuses in the same way like with moray eels. Participating species associate the presence of the other with a higher capture rate and thus optimize their individual hunting strategies.