In this study, freshwater crayfish (Astacus leptodactylus, Esch, 1823) eggs were incubated starting seven weeks after spawning, at three different temperatures (11.8 °C, 16±1°C and 20±l°C) and the results were compared with respect to hatching time and survival rate. The eggs hatched between days 116 and 125, 88 and 97, and 69 and 74, at 11.8 °C, 16 ±1 °C, and 20 ±1 °C, respectively. The survival rates at these temperatures were 22.4%, 46.9% and 32.5%. In conclusion, it was found that A. leptodactylus eggs could hatch 1.5 months earlier than under natural conditions by increasing water temperature, starting in March, up to 20 °C, but the optimum temperature for maximum hatching rate was found to be around 16°C.
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