Prey Catching in the Archer Fish: Marksmanship, and Endurance of Squirting At an Aerial Target

Abstract

Archer fishes (Toxotidae) can bring down aerial arthropods with a yet of water from their mouth. Although most authors seem to assume that squirting down prey is the archer fish's source of food, it has been suggested that this typical foraging technique can not play an important role because, among other things, the height at which a prey can be hit is limited, the fishes soon tire of squirting, and other kinds of food are eaten. Owing to lack of information or differences concerning methods, small numbers of subjects, and may be, differences between species, there is little agreement about the performance of the fish. In order to provide reliable data on marksmanship, endurance of squirting, and diet, the performance of Toxotes chatareus was observed during 25 weeks while the fishes (N = 16) got daily practice squirting at prey. The fishes readily took various kinds of food. Squirting was found to be effective in that the fishes, within 4,5 squirts and 41 seconds, reliably hit targets at a height up to eight times their body length. Contrary to earlier reports, the fishes were found to persist squirting at a fixed target eight times per minute during at least 10 min. The results concerning marksmanship, and endurance, indicate that, contrary to what has been suggested, squirting can be an important way of foraging in the natural habitat.