Strike tactics of Esox

Abstract

Strike tactics of a lunging piscivore attacking solitary prey were observed in an arena 50 cm long, 50 cm wide and 10 cm deep and recorded on television video tape. The predators were cultured tiger musky (Esox sp.). The prey were fathead minnow (Pimephales promelas). Predator strikes were S type fast starts allowing multidirectional attacks. Two strike patterns were observed. Pattern A strikes commenced from a stretched-straight body posture and progressed from fast start stage 1 through the normal 3-stage sequence. Pattern B strikes deleted the less efficient 1st stage, starting acceleration from an S posture. Strikes were directed in the vicinity of the center of mass of the prey, the point that moves least during escape attempts. Prey were usually attacked from the side, minimizing the displacement of the prey from the strike path after an escape attempt. Pattern A strikes were launched over distances from 3.8-33.9 cm and took 50-300 ms. Catch success was 42%. Pattern B strikes were used for short distances from 1.7-7.7 cm, taking 17-100 ms and were 95% successful. The observed strike tactics were those expected to maximize the probability of catching elusive fish prey.