Sockeye salmon for courtship. If they waste too much energy, they might not be able to spawn. Males must also make the decision whether to invest energy in fighting for a female or for longevity on the spawning grounds. Aggressive behavior displayed by dominant males is predominantly directed towards intruding dominant males. Sometimes sockeye salmon males behave aggressively towards subordinate males. These encounters are short, with the intruding male leaving after one or two aggressive interactions. Spawning females direct their aggression primarily towards intruding females or other spawning females that are close by. However, they may also direct aggression towards intruding or
Robot fish the speed of swimming will increase. It exhibits a state of shock and confusion to the foreign object much like a real fish would. Robot fish record this type of behavior in advance. Military defense and marine protection are of rising concern in the research field. As missions become more complicated, high-performance Autonomous underwater vehicle (AUVs) become necessary. AUVs require fast propulsion and multidirectional maneuverability. Robotic fish are more competent than current AUVs propelled by motion because the fish is a paradigm of bio-inspired AUV. Like living fish, robot fish can operate in complex environments. They can not only perform