As we have seen, the benefit of swimming behind a bluff body is not limited to using the region of reduced flow
relative to the earth frame of reference. Instead, the energy of individual, discrete vortices can be exploited. Vorticity control is a relatively new paradigm in fish locomotion and may help explain how migratory fishes can ascend highly turbulent rivers for extended periods. Harnessing the energy inherent in turbulent environments can be substantial; it has been experimentally and theoretically demonstrated that thrust can be generated entirely.