Shad is a tropical fish, which grows in fresh water or seawater with salinity lower than 10‰. The suitable temperature range is between 25-30℃. When the water temperature drops to 20℃, the food intake decreases obviously, and when the water temperature drops to 15℃, the body loses its balance, so the area where the pool water drops below 15℃ in winter is not suitable for the growth of baiji. During the wintering period, the water temperature of Managua was above 65438 09℃. Cichlasoma managuense is a carnivorous fish, which has strong carnivorous characteristics in the fry stage, mainly zooplankton.