How climate change may affect the early life stages of one of the most common freshwater fish species worldwide: the common carp (Cyprinus carpio)

The aim of the present study is to test the effects of temperature on the early life stages of one of the most common freshwater fish species worldwide, the common carp. About 16,000 eggs coming from 3-year-old broodstock were randomly distributed into five incubators, one incubator by tested temperature (16, 18, 20, 22, and 24A degrees C). Several parameters (survival and malformation rates, development time, morphometric parameters, and energy values) were studied at three key biological stages (hatching, emergence and first food intake). We found no significant impact of temperature on both survival and malformation rates. However, as expected, development time was three times longer at 16A degrees C than at 24A degrees C. At both 16 and 24A degrees C, the consumption of the yolk sac was highest; yet larvae were smaller at 16A degrees C and largest at 24A degrees C. Our results suggest that the early life stages of common carp developing at 22-24A degrees C could survive better in the wild, which is in accordance with current models that predict a small change of the distribution area of the common carp in France, but probably an extension in Northern European regions, in the next decades consequently to climate change.