Effects of Thermal Shock on Some Freshwater Fishes

Abstract

In order to understand the stress encountered by freshwater fish as a result of thermal discharges into waters, we undertake thermal shock experiments study. The TL 50 values of four freshwater fishes increased with increasing acclimation temperature. The UILT values for silver carp, bighead carp, grass carp and common carp were 37.1ć, 35.6ć, 37.7ć, 37.3ć, respectively. The results obtained showed similar type of heat acclimation for CTMax and LRR. Data of CTMax, LRR and TL 50 indicate the importance of acclimation temperature relative to their upper thermal tolerance limits of fishes. In fish acclimated at 30 ć , acute estimated final thermal optimum temperature was 29.9ć(silver carp), 31.2ć(bighead carp), 30.3 ć (grass carp) and 30.1 ć (common carp), respectively. The preferred temperature range of silver carp, bighead carp, grass carp, common carp was 28.0-32.0ć, 28.0-33.0ć, 27.0-34.0ć, 27.4-31.2ć.

Temperature Impact of the Industrial Cooling Water Discharges in a Long Boat Slip of Hamilton Harbour

“…High water temperature may cause concern due to the effect on surrounding aquatic life. However, the speed of water temperature change within a short period may be, sometimes, more sensitive for some species (Sheng and Xu 2008). For this reason the maximum temperature changes during the different time spans of 15, 30, 60, and 120 minutes have been calculated from all the measured temperature data, and are listed in Table 2.…”