Effect of temperature on growth, survival, thermal behavior, and critical thermal maximum in the juveniles of Macrobrachium occidentale (Holthuis, 1950) (Decapoda: Caridea: Palaemonidae) from Mexico

The effect of water temperature on growth, survival, and thermal behavior was studied in the juveniles of the prawn Macrobrachium occidentale (Holthuis, 1950) by exposing them to a replicate experimental design that included the complete temperature range in its natural environment. The optimal growth was between 25 °C and 28 °C. Survival was 100% at 22 °C, 97% at 28 °C, and 92% at 25 °C and 31 °C. The final thermal preference was 27.7 °C with no significant effect from acclimation temperature (Kruskall Wallis, P > 0.05). The different values for critical thermal maximum (CT_Max), depending on acclimation temperature, were 37.5 °C, 38.4 °C, 39.4 °C, and 40.8 °C, all were significantly different (ANOVA, P < 0.05). The calculated acclimation response ratio ranged from 0.37 to 0.53. These values agree with other values obtained for other decapod crustaceans from tropical and sub-tropical climates. This information aims to help understand the survival of Macrobrachium prawns facing temperature variations.