Effect of temperature and roach Rutilus rutilus group size on swimming speed and prey capture rate of perch Perca fluviatilis and R. rutilus

Abstract

Effects of temperature and group size of roach Rutilus rutilus on foraging behaviour of perch Perca fluviatilis and R. rutilus were tested in two laboratory experiments. A temperature experiment with P. fluviatilis and R. rutilus in aquaria (with either one P. fluviatilis or two R. rutilus) was tested at five temperatures: 4, 8, 12, 16 and 20 • C, and showed that P. fluviatilis had a lower swimming speed and capture rate than R. rutilus, especially at 4 and 8 • C. The effect of group size was tested at four R. rutilus abundances: 0, 2, 4 and 6, all at 16 • C, and revealed that swimming speed and capture rate of P. fluviatilis were lowest at the highest R. rutilus abundance, whereas R. rutilus was relatively unaffected. Perca fluviatilis occupied positions closer to the bottom than R. rutilus, especially when feeding, and this tendency was reinforced at the highest roach abundance.

Behavior of juveniles of roach Rutilus rutilus (cyprinidae), produced by breeders from a tributary of the Rybinsk Reservoir and from a nonfreezing area of the Moskva River at variable temperatures

“…Sharp changes in the values of most behavioral parameters were observed at temperatures below 12°С: e.g., no changes in feeding intensity were observed until the temperature reached 7.6°С, and the value of this parameter at 5.4°C was only 8% of its initial value, observed in the experiment with stable temperature. Similar results were obtained in experiments with the roach from natural waterbodies of Germany and southern Sweden, where the feeding intensity of the fish also decreased at temperatures below 12°C (Van Dijk et al, 2002: Hardewig and Van Dijk, 2003: Linlokken et al, 2010. This was explained by the decreasing activity of enzymes at these temperatures, especially of trypsin (Hardewig and Van Dijk, 2003).…”

Extrinsic and intrinsic factors influence daily activity of a Mediterranean cyprinid

“…These results are concordant with previous studies of fish activity patterns that demonstrate a relationship between diel activities and water temperature (Fraser et al 1993;Greenwood & Metcalfe 1998;Bremset 2000), however, few of these studies examined foraging behaviors in the field. In laboratory studies, search, capture rate and swimming characteristics (i.e., speed and angle of turn) may be positively related to temperature (Persson 1986;Marchand et al 2002;Linløkken et al 2010). Despite the strongly supported effect of temperature on searching behavior, its effect on foraging was weak, which may have been related to the low range of temperature values observed during the study.…”

“…; Linløkken et al. ). Despite the strongly supported effect of temperature on searching behavior, its effect on foraging was weak, which may have been related to the low range of temperature values observed during the study.…”

“…; Linløkken et al. ). However, the effects of temperature on activity may vary, with some species shifting from nocturnal to diurnal foraging as temperatures rise (Fraser et al.…”

“…Because fishes are ectotherms, they generally become more active when temperatures increase, either spending more time foraging or exhibiting faster swimming and attack rates (Weetman et al 1998;Marchand et al 2002;Linløkken et al 2010). However, the effects of temperature on activity may vary, with some species shifting from nocturnal to diurnal foraging as temperatures rise (Fraser et al 1993;Greenwood & Metcalfe 1998;Breau et al 2007), although many species retain fairly constant activity patterns regardless of temperature (Gries et al 1997;David & Closs 2003;Baktoft et al 2012).…”