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The carp is a large fish, which can measure up to 1.2 meters and weigh up to 40 kilos. When mating they can even come out of the water, as we can see in this image that I captured in the Sau reservoir for Las Fotos de los Lectores de La Vanguardia.
It is a freshwater fish and, although it has been in the Sau swamp for many years, it is an introduced species. Despite the fact that there was talk of the emptying of fish from the swamp due to the drought to transfer the remaining water to Susqueda, the carp is still clearly visible, as we see in the photograph.
In fact, the Sau reservoir is already at 22.88% of its capacity, although a year ago it was at 56.80% and the average for the last five years is 131.33%.
The carp breeding season begins in spring and ends at the beginning of summer. They prefer shallow water, with a dense vegetation cover.
The females lay their eggs in the undergrowth and the male fertilizes them externally. The eggs remain attached to the substrate until they hatch. It is estimated that a female can lay up to 1,000,000 eggs, although the average for an adult female is 300,000.
The time it takes for the eggs to hatch is related to the temperature of the water. With a good incubation (water at 30 °C), they hatch after three days.
Males normally reach sexual maturity earlier than females, although for both sexes it is around four years.
