Thermal Tolerance of Turkish Crayfish (Astacus leptodactylus) Acclimated to Three Different Temperatures

Abstract

Critical thermal maxima (CTMax) and minima (CTMin) were determined for Turkish crayfish (Astacus leptodactylus) acclimated to 15, 20 and 25°C. CTMin and CTMax were 1.3, 1.1 and 2.0°C, and 37.4, 37.5 and 38.7°C, respectively. Thermal tolerance tests showed that acclimation temperatures (15, 20 and 25C) had significant effects on CTMin values of A. leptodactylus (P≤0.05). The area of thermal tolerance assessed using the CTMin and CTMax boundaries were calculated as 364°C 2. The overall ARR values were calculated as 0.07 for CTMin and 0.13 for CTMax values between 15 and 25 C acclimation temperatures. All the crayfish crumpled at 0.5°C and showed overall spasm at 32.0-33.0°C. Farming A. leptodactylus in the southeastern part of the Mediterranean region may be practiced in terms of temperature tolerance.