Effects of phytoplankton-induced turbidity on predation success of piscivorous Eurasian perch (Perca fluviatilis): possible implications for fish community structure in lakes

Abstract

Turbidity can strongly influence predation success of visually oriented fish, especially piscivores such as adult Eurasian perch (Perca fluviatilis). This purely carnivorous species usually becomes a facultative piscivore after two discrete food niche shifts. Perch biomass has been observed to decrease in lakes along the productivity gradient, and then be replaced by cyprinids in non-manipulated eutrophic systems. Until now, this change has been mainly attributed to the competitive superiority of cyprinids for zooplankton prey during the juvenile phase of perch, while the piscivorous phase--as a possible factor influencing the recruitment success of perch--has been neglected. As the abundance of suitably sized prey fish should not be limiting in highly productive systems, we hypothesise that the switch from benthivorous feeding to preying on fish is inhibited by the reduced visibility in eutrophic lakes. We tested this hypothesis in laboratory experiments, where perch were fed two size classes of juvenile cyprinids at different phytoplankton- and bentonite-induced turbidity levels. Predation success was significantly influenced by turbidity level and turbidity source, but not by prey size. These experimental results suggest for the first time that piscivory of Eurasian perch is negatively influenced by different sources of turbidity, and hence low visibility might delay the onset of the food niche shift to fish prey.

Prey detection by great cormorant (Phalacrocorax carbo sinensis)in clear and in turbid water

“…This holds true for visually mediated interactions between species such as predation (Radke and Gaupisch, 2005;Van de Meutter et al, 2005) and within species such as courtship (Endler, 1987;Endler, 1991;Seehausen et al, 1997). At the air-water interface light is refracted and reflected with light intensity underwater declining and its chromatic composition shifting (Lythgoe, 1979;Loew and McFarlend, 1990;Loew, 1999).…”

“…Abrahams and Kattenfeld, 1997;Radke and Gauspisch, 2005) or to other visual stimuli. Moreover, the effects of turbidity, an all-important determinant of underwater vision (Gazey, 1970;Lythgoe, 1979;Aksnes and Giske, 1993;Vogel and Beauchamp, 1999;Radke and Gaupisch, 2005), have been surprisingly little studied within this general framework.…”

Risk-sensitive mating decisions in a visually compromised environment

“…The level of turbidity simulated in our experiment falls within the range reported in the Baltic during the sand goby breeding season (Granqvist & Mattila 2004) and is comparable to that used in other studies in which reproductive activities have been affected (Järvenpää & Lindströ m 2004). In particular, similar levels of turbidity have previously been shown to reduce the capture success of visually oriented predators such as perch (Radke & Gaupisch 2005). However, by reducing visibility in the water column, such conditions also compromise visual cues that are relied upon by sand gobies ( Järvenpää & Lindströ m 2004).…”

“…Here, we set out to compare the latency to spawning in sand gobies in both the presence and absence of a visually oriented piscivorous predator, the European perch (Perca fluviatilis), under both clear and turbid water conditions. Algal turbidity greatly diminishes the predation success of perch by reducing visibility in the water column (Radke & Gaupisch 2005), but is also likely to compromise the efficacy of visual cues available to sand gobies (Järvenpää & Lindström 2004). Sand gobies are therefore an excellent model for investigating the effects of algal turbidity and predation risk on reproductive decisions.…”

Effects of turbidity and light intensity on foraging success of juvenile mandarin fish Siniperca chuatsi (Basilewsky)

“…Increased turbidity can have negative effects on the foraging success of fish (Gregory 1993;Miner and Stein 1993;Gregory and Levings 1998;Radke and Gaupisch 2005;Pekcan-Hekim and Lappalainen 2006;Carter et al 2010), but does not affect the foraging success of some species (Bergman 1988;Vandenbyllaardt et al 1991;Reid et al 1999;Granqvist and Mattila 2004), and can even enhance foraging efficiency (Gregory and Northcote 1993). Little is known on the combined effects of turbidity and light on predation of juvenile piscivorous fish, and no information is available on juvenile mandarin fish.…”