Altered aggression in different sized groups of crayfish supports a dynamic social behaviour model

Abstract

Living in groups with conspecifics can increase an animal's fitness in the wild. A social environment may also be imposed by commercial farming industries. One important measure of competition and group dynamics is the level of aggressive interaction. This can also influence the level of damage or injury in cultured populations, a commercial issue at point of sale. There is considerable research into this issue in commercial species such as pigs, cattle and chickens but less is known about aquatic communal species such as decapod crustaceans. Here we manipulated group size in the freshwater crayfish Cherax destructor, a species that forms social groups in the wild and one that is also commer..