Rotlachs
Sockeye salmon use patterns of limnetic feeding behavior, which encompasses vertical movement, schooling, diel feeding chronology, and zooplankton prey selectivity. They can change their position in the water column, timing and length of feeding, school formation, and choice of prey to minimize the likelihood of predation. This also ensures they still get at least the minimum amount of food necessary to survive. All of these behaviors contribute to the survivability, and therefore fitness of the salmon. Depending on location and threat of predation, the levels of aggressive feeding behavior can vary.