Thermal dependence of swimming endurance in juvenile brown trout

Abstract

The maximum swimming stamina of hatchery reared juvenile brown trout Salmo trutta, swimming against a fixed-velocity water flow of 36·6 cm s 1 (6·97 L s 1 ), was achieved at 16·1 C, and a 90% performance level occurred over a breadth of 7·7 C (12·2-19·9 C). The wide range of temperatures at which swimming performance is close to the maximal capacity could be a consequence of the implications for survival of this function. 2000 The Fisheries Society of the British Isles

Factors influencing the spawning migration of female anadromous brown trout

“…Several lines of evidence indicate that diadromous salmonids may be subjected to important predation during migrations while in fresh water (Mather, 1998). The swimming ability of fishes is reduced in cold water (Videler, 1993; Ojanguren & Brana, 2000), which make sea trout more vulnerable to predation by endothermic predators (Heggenes et al ., 1993). Potentially, this was enhanced in the present study because gravid fish may be more vulnerable to predation (James & Johnston, 1998).…”

“…This study revealed an interaction between water temperature, discharge and the probability of sea trout initiating upstream migration, indicating a positive correlation between temperature and the probability of upstream migration ‘initiation’ at equal discharges. This is presumably due to the increased swimming ability (Videler, 1993; Ojanguren & Brana, 2000; Heggenes & Dokk, 2001) and activity (Beamish, 1978; Ojanguren et al ., 2001) of fishes in warmer water, as temperature approaches the thermal optimum for locomotor activity. Hence, the probability of upstream migration ‘initiation’ is positively correlated with discharge, but the distance swum during the spate is positively correlated with temperature.…”

Effect of growth compensation on subsequent physical fitness in green swordtailsXiphophorus helleri

“…Fishes were deemed to be exhausted when they were forced back against the back fine mesh grid for more than 5 s (Ryan 1988) and were no longer able to continue swimming, despite tapping of the side of the chamber (Ojanguren & Brañ a 2000). Once exhausted, the pump was turned off and the fish allowed 5 min recuperation time before being placed back in its rearing tank.…”

Effect of temperature on swimming performance of sea bass juveniles

“…The response curve of prolonged swimming speed to water temperature typically has the form of a performance curve with the highest values at the optimum and decreasing at the upper or lower thermal range (Beamish, 1978;Myrick & Cech, 2000;Ojanguren & Brana, 2000). The present study showed that sea bass juveniles follow the characteristic model of U crit dependence on temperature, with 24·4 C as the optimum temperature and with a wide thermal range of c. 10 C (19·3-29·6 C), in which performance is >90% of the maximum U crit (Fig.…”

“…3). The maintenance of high swimming performance over a broad thermal range is very important for juvenile survival in nature, since it affects predator avoidance and prey capture (Fuiman, 1991;Blaxter, 1992;Temple & Johnston, 1998;Ojanguren & Brana, 2000). This is especially important in fishes such as sea bass, which inhabit shallow lagoons and estuaries during the juvenile T II.…”