Preliminary Study On The Aggressive Behavior And Social Hierarchy Of Captive Egretta Eulophotes In Non-breeding Period

Egretta eulophotes is gregarious animal, in which aggressive behavior and social hierarchy are very important to its’gregarious life. This experiment preliminarily described and analyzed the aggressive behavior, social hierarchy model and establishment of the social hierarchy of captive Egretta eulophotes on the Xiamen Egret Nature Reserve of Dayu Island. The obersrved aggressive behavior of Egretta eulophotes included threat, appeasement, ritualized fighting and submissive behavior. The experiment samples are11Egretta eulophotes in total, including3males and6femles borned in2013on Caiyu island, and2femles borned in2013on the Xiamen Egret Nature Reserve of Dayu Island. These Egretta eulophotes were taken when the nestlings just could leave the nest, and reared in cages on the Xiamen Egret Nature Reserve of Dayu Island. After3months of adaptive experiment, the formal observations were made from October2013to January2014.The results by analyzing different groups of the aggressive behavior of captive Egretta eulophotes indicated that there were some differences of aggressive behavior in different densities, populations, sexes or genetic relationships. The aggressive behavior of captive Egretta eulophotes was significant difference in different densities, in which the higher density in cages, the more aggressive behavior happened. For different populations, more aggressive behavior were observed between the populations of Egretta eulophotes come from different places. Also, the aggressive behavior differences were found in gender, which male Egretta eulophotes were more aggressive and had stronger territoriality than females. Futhermore, genetic relationships could influence the aggressive behavior of captive Egretta eulophotes, which the displays of aggressive behavior would be significantly decreased in genetically related individuals.Our oberservation found that the mode of social hierarchy in Egretta eulophotes was linear. The time for Egretta eulophotes to establish a social hierarchy was between10to90days. Th factor mainly influence the social hierarchy establishment in Egretta eulophotes was the physical parameter of individual, and aggressive behavior had some effect on the the social hierarchy of Egretta eulophotes.