Animal behavior is a direct response of animal to external stimuli and is one of the most important properties of animal life.The behavior of animals often provides first clue of environmental degradation.Animal behavior is one of most fundamental disciplines of biology,which is applied to all aspects of aquaculture,including domestication and captive rearing,selective breeding,health monitor,preparing formulated feed,feeding,reproduction,larval metamorphosis,habitat selection,fighting and aggression,polyculture,and rearing system design.