Abstract: This paper reported the variousbehaviours in two male Amaron dolphins,named" Vater" and " Baby",which had been kept at the Duisburg Zoo for 16 vears.Thebehaviour of the dolphins in captivity is directly affected by the size of the pool.Differetspecies of dolphins,with different body structures and in different habitat characteristics,have different behaviours:"Vater" and "Baby" show closer relations for emotional andphysiological factors since they have lived together for 16 years.