Changes in Prey Rank and Preference by Young Planktivores for Short-Term and Long-Term Ingestion Periods

Abstract

New b r k 14850, USA Confer# I. L., and L. M. O' Bryan. 1989. Changes in prey rank and preference by young planktivores for shortterm and long-term ingestion periods. Can. ). Fish. Aquat. Sei. 46: 1026-18132.Feeding by young planktivorous fishes (yellow perch, Perca fhveseens, rainbow trout, Oneorhydeeheds mykiss, and lake trout, Sa%veliwus narnaycush) was examined. Prey rank was determined by offering a swarm sf one prey type and observing ingestion rates. During the initial feeding burst, larger prey generally ranked higher. During Bong-term feeding the largest prey, large Daphwia rnagna, generally declined in rank while the smallest prey, Diaptomur sicilk, increased to the highest sr second highest rank. Prey preference was measured with fishes feeding in a swarm of mixed prey. Initially small rainbow trout and yellow perch selected for large Daphnia then switched to Biaptamrcs. For small rainbow trout this switch in prey preference paralleled the change in prey rank. For yellsw perch, large Daphnia and Dbaptomus provided essentially the same long-term ingestion rates. The nearly exclusive selection for Diaptorness during long-term feeding did not agree with prey rank based on caloric ingestion rates. Previous work has shown that yellow perch have a high growth efficiency on a diet of Diaptomus. Selection for Diaptomus suggests that fish can rank prey by nutritional quality as well as calorie ingestion rates.Calimentation de jeunes poissons pianetivores (Perca d8avescews, Oneoryhnchus mykiss, et Salve%inus namaycush) a et$6tudi6ee L'ordre de consommation des proies a kt4 dkterminee en offrant un essairn d'organismes appartenant 2 un type de proie et en observant le taux d'ingestion. Pendant la poussee initiale d'alirnentation, les grosses prsies occupaient en g4neraI les prerni&res places, comme Daphnia magna, oceupaient en general un rang inf4rieur tandis que [es petites proies comme Diaptornus sicd%is atteignaiewt la prernigre ou la seconde place. La pr4ference des proies a 686 rnesuree chez des poissons se nsurrissant dans un essairn de proies m&lang4es, Au debut, les truites arc-en-ciel et les perchaudes de petite taille se nourrissaient de Dapkriia de grande taille, puis de Dbaptomus. Dans le cas de la truite arc-en-eiel de petite taiile, ce changernent de preference etait para!%&le au changernewt de rang des proies. Dans B e cas de la perchaude, les Daphnia et les Diaptomems de gragzde taille fournissaient essentiellement %e m$me taux d'ingestion A long terme. Le ckoix presque exrlusif de Diapbrnus pendant la periode dklimentation A long terme ne concordait pas avec le rang des proies etabli ew fsnction du taux d'ingestion de calories. Des travaux anterieurs ont rnontre que la croissance de la perchaure etait plus grande lorsqu'elle se nsurissait de Diaptomus. Le choix de Diaptamus porte 2 croire que les poissons peuvent choisir leur proie en fonctisn de la qualit6 nutritionnelle aussi bien qukn fonction du taux d'ingestion de calories. (J9720)umerous studies o f feeding by p l d t i v o r o u s fishes h...

Diet composition and food selectivity of 0-group herring (Clupea harengusL.) and sprat (Sprattus sprattus(L.)) in the northern Baltic Sea

“…When fish increase in size, the size spectrum of ingested prey increases, probably an effect of less gape-size limitation (Miller et al, 1988;Schael et al, 1991). The present data show preferences for intermediate sized prey (mostly copepodite stage IV-V, 0.7-1.0 mm), which agrees with others studies on herring (Munk, 1992) and other planktivores (Bence and Murdoch, 1986;Confer and O'Bryan, 1989;Graham and Sprules, 1992). However, for adult herring, one of the largest zooplankton items in the Baltic, Limnocalanus spp.…”

“…This variation in length of fish and prey influences the relationship between foraging selectivity and relative prey size as seen in other studies on clupeoids (Checkley, 1982;Cohan and Lough, 1983;Raid, 1985;Lankov, 1986;Wespestad and Moksness, 1989;Conway et al, 1991;Munk, 1992). In other planktivores prey size is also positively correlated with fish size (Mills et al, 1984;Bence and Murdoch, 1986;Confer and O'Bryan, 1989;Shael et al, 1991). When fish increase in size, the size spectrum of ingested prey increases, probably an effect of less gape-size limitation (Miller et al, 1988;Schael et al, 1991).…”

Differences in feeding selectivity and efficiency between young-of-the-year European perch (Perca fluviatilis) and roach (Rutilus rutilus) — field observations and laboratory experiments on the importance of prey movement apparency vs. evasiveness

“…However, field observations and laboratory experiments with perch, both European Perca fluviatilis (Furnass 1979;Rajasilta & Vuorinen 1983) and its close relative North American P. flavescens (Mitchill, 1814) (Mills et al 1987;Confer & O'Bryan 1989), have shown that under specific circumstances these fish have behaved differently from the general scheme of Daphnia preference and contrastingly have selected the evasive cyclopoid and even more evasive calanoid copepods. Perch have done so particularly in long time feeding experiments or at high prey densities, i.e.…”

Piscivory and prey size selection in young-of-the-year bluefish: predator preference or size-dependent capture success?

“…USA prey are preferentially consumed (Brooks & Dodson 1965, Werner & Hall 1974, while others have shown the reverse (Bence & Murdoch 1986, Walton et al 1992. Confer & O'Bryan (1989) demonstrated that size selectivities of planktivorous fish depend on whether feeding is averaged over short or long time periods. These widely varying results have led to a debate about whether 'preferences' represent active (Mittlebach 1981, Werner et al 1983 or passive (O'Brien et al 1976, Maiorana 1981) choices, and the reasons for differential prey vulnerabilities (Pastorok 1981, Dunbrack & Dill 1983, Greene 1983).…”