Assessment of Electrofishing Effects on Gambosia holbrooki Girard, 1859 in a Controlled Environment (Salinity and Temperature)

The purpose of this study was to investigate the effect of voltage, salinity and temperature on the performance of electric fishing. To do so, 850 pcs Gambosia holbrooki from Golestan dam were hunted and transported to the laboratory. Distance from the anode, cathode and anode distance during testing were 10cm and 120cm, respectively. Experimental fish length and weight range for this species were calculated 3.818 ± 0.20 cm and 0.804 ± 0.135 gr , respectively. Electric shocks were applied to individual fish in three voltages of 15, 45 and 135 volts and 3 °c, 10 °c, 20 °c and 30 °c, and 3 salinity of 0.5, 2 and 4 g/l. Time to pass out and return to the initial state for individual fish were recorded. Statistical analysis of ANOVA, Duncan and LSD showed that the average duration of voltages and temperatures and salinities of anesthesia obtained are significantly different. The maximum and minimum anesthesia time were calculated for the Gambosia holbrooki from the salinity of 0.5, 10° c, Voltage 15, with a mean of 8.71 ± 0.74s and from the salinity of 4, 30° c, Voltage 135, with a mean of 1.44 ± 0.32s, respectively. The maximum and minimum reset time for Gambvzya were resulted from the salinity 0.5, 10° c, Voltage 135, with a mean of 94.84 ± 3.1s and the salinity of 0.5, 30° c, Voltage 15, with a mean of 20.01 ± 2.72 s, respectively.