“Alewives swimming upstream flash of silver and also muscling themselves up steep  inclines In riffling areas of shallow water.. “With an acute understanding of physics, the alewives turn on their sides and swim sideways up the ledges to maximize the surface area of their tails against the current and then right themselves as soon as the water gets deeper. When the current is hard they will swim so fast they shoot out of the water, not to jump, but because their momentum carries them out of the water and into the air”

Watts, Douglas. Alewife. Augusta: Poquanticut Press, 2012. pp. 12-13.