The relationship between the snowmelt flood and the establishment of non-native brown trout (Salmo trutta) in streams of the Chitose River, Hokkaido, northern Japan

2013 ◽  
Vol 22 (4) ◽  
pp. 645-653 ◽  
Author(s):  
Hideyuki Kawai ◽  
Nobuo Ishiyama ◽  
Koh Hasegawa ◽  
Futoshi Nakamura
2013 ◽  
Vol 70 (2) ◽  
pp. 280-293 ◽  
Author(s):  
Theodore Castro-Santos ◽  
Francisco Javier Sanz-Ronda ◽  
Jorge Ruiz-Legazpi

Sprinting behavior of free-ranging fish has long been thought to exceed that of captive fish. Here we present data from wild-caught brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta), volitionally entering and sprinting against high-velocity flows in an open-channel flume. Performance of the two species was nearly identical, with the species attaining absolute speeds > 25 body lengths·s−1. These speeds far exceed previously published observations for any salmonid species and contribute to the mounting evidence that commonly accepted estimates of swimming performance are low. Brook trout demonstrated two distinct modes in the relationship between swim speed and fatigue time, similar to the shift from prolonged to sprint mode described by other authors, but in this case occurring at speeds > 19 body lengths·s−1. This is the first demonstration of multiple modes of sprint swimming at such high swim speeds. Neither species optimized for distance maximization, however, indicating that physiological limits alone are poor predictors of swimming performance. By combining distributions of volitional swim speeds with endurance, we were able to account for >80% of the variation in distance traversed by both species.


2000 ◽  
Vol 57 (10) ◽  
pp. 2086-2095 ◽  
Author(s):  
Kim Aarestrup ◽  
Christian Nielsen ◽  
Steffen S Madsen

The relationship between smolt status and downstream movement following release was investigated in two stocks of hatchery-reared anadromous brown trout (Salmo trutta). Yearlings from a domesticated stock (DS) and first-generation offspring (F1) of wild anadromous trout were held under identical conditions from August 1997 until the following spring, where they developed smolt characteristics as judged from increasing gill Na+,K+-ATPase activity. Presmolts (low Na+,K+-ATPase activity), smolts (high Na+,K+-ATPase activity), and desmolts (regressed Na+,K+-ATPase activity) were released on three occasions into the River Salten. Using both dye-marked and radiotagged fish, downstream movement was monitored by either trapping 3 km downstream (dye-marked fish) or radiotracking on a daily basis. The experiments showed a positive correlation between smolt status (gill Na+,K+-ATPase activity) and downstream movement. Gill Na+,K+-ATPase activity may therefore be used as an indicator of migratory readiness in brown trout. F1 and DS trout had the highest migration frequency when released as presmolts and smolts, respectively. Despite smaller size, F1 trout had similar or better survival than DS trout after release. Our data suggest that initiation of downstream movement is influenced by an interaction between the previous physiological development of the fish and a discrete level of water discharge or water temperature.


1993 ◽  
Vol 177 (1) ◽  
pp. 293-297
Author(s):  
P. J. Butler ◽  
N. Day

Early studies on reptiles demonstrated that plasma pH increases as body temperature falls (Robin, 1962). Rahn (1967) proposed that plasma pH in all poikilothermic vertebrates is regulated as body temperature changes so as to maintain a constant relative alkalinity, i.e. a constant [OH-]/[H+] ratio, and Reeves (1972) suggested a way in which this could be achieved. Known as the ‘imidazole alphastat hypothesis’, it postulates that PCO2 is regulated (by way of ventilation) so that the fractional dissociation (alpha) of the imidazole moiety of histidine is kept constant. As the pK' of imidazole changes with temperature in about the same manner as the neutral pH of water (Heisler, 1986), the alphastat hypothesis is consistent with that of constant relative alkalinity.


2011 ◽  
Vol 14 (3) ◽  
pp. 443-448 ◽  
Author(s):  
N. Kurhalyuk ◽  
H. Tkachenko ◽  
K. Pałczyńska

Resistance of erythrocytes from Brown trout (Salmo trutta m. trutta L.) affected by ulcerative dermal necrosis syndrome In the present work we evaluated the effect of ulcerative dermal necrosis (UDN) syndrome on resistance of erythrocytes to haemolytic agents and lipid peroxidation level in the blood from brown trout (Salmo trutta m. trutta L.). Results showed that lipid peroxidation increased in erythrocytes, as evidenced by high thiobarbituric acid reactive substance (TBARS) levels. Compared to control group, the resistance of erythrocytes to haemolytic agents was significantly lower in UDN-positive fish. Besides, UDN increased the percent of hemolysated erythrocytes subjected to the hydrochloric acid, urea and hydrogen peroxide. Results showed that UDN led to an oxidative stress in erythrocytes able to induce enhanced lipid peroxidation level, as suggested by TBARS level and decrease of erythrocytes resistance to haemolytic agents.


2021 ◽  
Vol 29 ◽  
pp. 100675
Author(s):  
Muhammed Atamanalp ◽  
Arzu Ucar ◽  
Esat Mahmut Kocaman ◽  
Gonca Alak

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