Freshwater percid (Percidae) fish can be divided into the two groups depending on type of their activity and sensory equipment. European perch, Perca fluviatilis, American yellow perch, Perca flavescens, and numerous American darters (Etheostoma) demonstrate the diurnal type of activity (first of all of the feeding activity), are visually guided fish and, thus, may be included in the first group.

In laboratory and natural conditions, both perches usually do not eat immobile as well as dead food and demonstrate relatively weak responses to food odors or their absence. According to Mirza et al. (2003), an aqueous brine shrimp (Artemia spp.) extract (5 g of frozen shrimp in 150 ml of distilled water for 1 hour) induces searching movements in P. flavescens. Both perches, however, do not go practically into the minnow traps baited with the animal lures (in contrast to cyprinid, cobitid and other fish).

In aquarium, blinded P. fluviatilis may find the pieces of earthworms using olfactory and gustatory systems (Wunder, 1927). But convergence of perch with brown trout, Salmo trutta, on sensory system utilization is incorrect.

Both species of euryhaline Percarina, Azov percarina, P. maeotica, and common percarina, P. demidoffi, use vision in day when hunting for zooplankton and lateral line system at night when hunting for preyfish (Kanaeva, 1956).

Roberts and Winn (1962) have tested utilization of the senses in feeding behavior of johnny darter, Etheostoma nigrum, using live worms (Tubifex), dead worms and crushed worm solutions. It is shown that darters prefer live worms and respond slightly to an olfactory stimulus. Daugherty et al. (1976) have studied responses of six species of darters (E. gracile, E. spectabile, E. whipplei, E. radiosum, E. collettei and E. punctulatum) to visual and olfactory cues of worms. It is revealed that olfactory cues (water from live Tubifex) alone are not sufficeint to stimulate complete feeding behaviour in darters, both in clear or muddy waters.

Fountain darter, Etheostoma fonticola, respond to live aquatic microinvertebrates and ignore immobile items (Shenck & Whiteside, 1977).

Darters or longperches of Percina genus are also diurnally active and feed on live macroinvertebrates (Greenberg, 1991). Percina are more mobile than Etheostoma and spent most time above the bottom.

Another group is formed by percids with the twilight or nocturnal type of feeding activity with the well developed chemosensory and lateral line systems. Three Europen zander ... Read more »