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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 day 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.

Skin of percid fish contains alarm pheromone that is documented in yellow perch P. flevescens, common ruffe Gymnochephalus cernuus and other species. Releasing in the water, this pheromone induces in small (planktivorous) perch an avoidance behaviour, whereas large (piscivorous) perch display feeding behaviour (Mirza et al., 2003; Harvey & Brown, 2004).


Another group is formed by percids with the twilight or nocturnal type of feeding activity with the morphologically developed chemosensory and lateral line systems. Three Europen zanders or pikeperches, Stizostedion lucioperca , S. volgensis and estuarine pikeperch S. marinus, both North American zanders, walleye S. vitreus and sauger S. canadensis, all species of Gymnocephalus genus (such as common ruffe G. cernuus, Donets ruffe G. acerina, striped ruffe G. schraetser and other), all species of Zingel genus (such as Z. zingel, Z. streber, Z. balcanicus and other) and sculpin-perch Romanichthys valsanicola (single species of Romanichthys genus) belong to this group. Three last genera are represented in temperate Europe, except common ruffes which occupy mainly boreal areas around the world being active intruders in America.

Underyearling walleyes are mainly visually guided fish with the olfactory system that can detect individual chemicals and artificial food odors (Rottiers & Lemm, 1985). In particular, fish are attracted by amino acids (arginine), betaine, washings from live Daphnia and Artemia but reject many other chemicals (cysteine, glycine, glycine-betaine).

According to Valentinčič (2004), walleyes and some other fish occupy an exclusive niche of visually guided predators with the secondary role of chemosensory system in feeding behaviour. Electrophysiological dara indicate that olfactory system of walleyes is broadly tuned while gustatory system of them is tuned very narrowly. On the other hand, behaviuoral data for wild walleyes show that over 90 % of fish do not use chemical senses to release feeding excitatory state. In addition, walleyes which are not conditioned to eat nonliving foods during their early life do not use olfactory and taste systems to control feeding bahaviour (Valentinčič, 2004).

The olfactory sensitivity of nocturnal percid fish to foo ... Read more »

Category: Attractants | Views: 1360 | Added by: nickyurchenko | Date: 2013-06-30

Northern pike, Esox lucius, are attracted by alarm pheromone of fathead minnow, Pimephales promelas, deposited normally in the undamaged fish skin (Mathis et al., 1995; Chivers et al., 1996; undirect data by Wisenden & Thiel, 2001). According to Mathis et al. (1995), pike are also attracted by an artificial hypoxanthin-3(N)-oxyde identified as an active component of the Ostariophysi alarm pheromones.

In addition to pike in the winter experiments (Wisenden & Thiel, 2001), other predatory fish active in cold season such as walleye, Stizostedion vitreum, largemouth bass, Micropterus salmoides, and yellow perch, Perca flavescens, might be attracted by the skin extract of fathead minnow, P. promelas. Other potential predators in the experimental locality (Wisenden & Thiel, 2001) such as black bullhead catfish, Ameiurus melas, brown bullhead, A. nebulosus, and yellow bullhead, A. natalis, are inactive in the winter season.

It is shown directly that piscivorous (adult) largemouth bass, M. salmoides, are attracted by alarm pheromone of finescale dace, Phoxinus neogaeus (Brown et al., 2001). Likewise, adult yellow perch, P. flavescens, are attracted by conspecific alarm pheromone (Hurvey & Brown, 2004) while juvenile (planktivorous) bass and perch demonstrate anti-predator behaviour to the same cue.

According to Mathis et al. (1995), skin extract of fathead minnow, P. promelas, attracts also 6 species of predaceous diving beetles (Dytiscidae) like Colymbetes sculptilis and more.

Basic References

Brown G.E., LeBlanc V.J., Porter L.E. 2001. Ontogenetic changes in the response of largemouth bass (Micropterus salmoides, Centrarchidae, Perciformes) to heterospecific alarm pheromones. Ethology 107, 401-414

Chivers D.P., Brown G.E., Smith R.J.F. 1996. The evolution of chemical alarm signals: attracting predators benefits alarm signal senders. The American Naturalist 148, 649-659

Harvey M.C., Brown G.E. 2004. Dine or dash?: Ontogenetic shift in the response of yellow perch to conspecific alarm cues. Environmental Biology of Fishes 70, 345-352

Mathis A., Chivers D.P., Smith R.J.F. 1995. Chemical alarm signals: predator detterents or predator attractants? American Naturalist 145, 994-1005

Wisenden B.D., Thiel T.A. 2001. Field verification of predator attraction to minnow alarm substance. Journal of Chemical Ecology 28, 417-422

Category: Attractants | Views: 1109 | Added by: nickyurchenko | Date: 2013-06-30



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