Some Irrawaddy dolphins used to be sighted only along the inlet channel and in a limited portion of the central sector of the lake. After the opening of the new mouth at Satapada in 2000, they are now well distributed in the central and the southern sector of the lake. The number of dolphins sighted has varied from 50 to 170. A 2006 census counted 131 dolphins and the 2007 census revealed 138 dolphins. Out of the 138 dolphins, 115 were adults, 17 adolescents and six calves. 60 adults were spotted in the outer channel followed by 32 in the central sector and 23 in the southern sector.