Feeding ecology and prey selection of European perch,Perca fluviatilisinhabiting a eutrophic lake in northern Turkey

Abstract

Feeding habits and prey selection of European perch (Perca fluviatilis) were examined in Lake Ladik between November 2009 and October 2010. Stomach contents of 308 individuals ranging in size from 73 to 275 mm total length were analyzed and 55.2% were empty. The fullness index indicated that feeding intensity of this species was the highest in summer and the lowest in winter. European perch feeds on prey fish and macroinvertebrates. The most important food items were Scardinius erythrophthalmus and Perca fluviatilis, followed by chironomidae larvae. Diet composition and feeding habits varied seasonally and ontogenetically. Macroinvertebrates were only consumed by small individuals, while prey fishes were only eaten by large individuals. S. erythrophthalmus, P. fluviatilis, and Blicca bjoerkna were positively selected but their selection indexes were not statistically significant (p > 0.05). This prey selection is important for combating eutrophication. Abramis brama constitute 24.03% of all fish species in this lake; however, it was a negatively selected prey item (V a D ¡0.198, x 2 D 7.86, p < 0.05). Esox lucius, Squalius cephalus, Chondrostoma regium, and Carassius gibelio inhabiting this lake were not preferred by European perch. Cannibalism rate was 12.3%.

The diet of predatory fish in drinking water reservoirs – how can they contribute to biomanipulation efforts?

“…Considering the regular occurrence and relatively high rate of conspecific predation recorded in our own (15 %m) and other studies (e.g. 12.3 % in Yazicioglu et al 2016), the role of perch in biomanipulation efforts becomes questionable. As a general conclusion, we would suggest that the role of perch is to be assessed on a case-by-case basis, taking full account of the time of year and, especially, the current status of perch recruitment.…”

Interannual variability in the trophic niche of young‐of‐year fish belonging to four piscivorous species coexisting in a natural lake

“…October was chosen as the sampling period because SIA of fin tissues (detailed below) is integrative of the three previous months (Busst & Britton, 2018; Willis et al, 2013), corresponding to the summer period. The feeding intensity is usually very high in summer (Balik et al, 2006; Copp et al, 2009; Dominguez & Pena, 2000; Yazıcıoğlu et al, 2016), which encompasses the important growth period of YOY in northern temperate lakes before winter (Kubečka, 1994; Nunn et al, 2002). Fish were caught using fyke nets set equally in the pelagic and littoral zones, and using fish traps and electrofishing in the littoral zone.…”

Predatie van glasaal nabij kunstwerken : een veldonderzoek bij de gemalen De Waker, Halfweg en Spaarndam langs het Noordzeekanaal

“…Binnen de studie is slechts bij twee baarzen waargenomen dat er vis was gegeten en betrof dit visresten (graten), kolbei/brasem en driedoornige stekelbaars. Vanaf circa 14 cm begint baars vis te eten zoals brasem, kolblei, ruisvoorn en kleine baars (Yazicioglu et al 2016) (Dorner et al 1999, Dorner et al 2003, Ribeiro et al 2021.…”