Bhubaneswar: The Chilika Development Authority has decided to set up a permanent station at the mouth of the lagoon to study migratory behaviour of Irrawady dolphins whose count slipped by 11 during this year`s census, official sources said.
The annual census of Irrawady dolphins, conducted over 1100 sq km of the lake on January 16 and 17, revealed that the head count had been 145 against last year`s census figure of 156.
"The slight reduction of estimated number could be due to the migration of the species from lake to the sea," CDA Chief Executive A K Patnaik said.
Stating that it is proposed to install a permanent station at the mouth of the lake equipped with highly efficient hydrophone array developed by the Tokyo University, Patnaik said an MoU had already been signed with it.
The university scientists will be coming to Chilika during April 2012.
Once the station is installed at the mouth, the movement of the dolphin can be definitely known, he said.
With about 10 per cent reduction in the population of the rare species, Patnaik said "so far it could not be established based on the visual observations whether the number dwindled due to migration".
Patnaik said that they suspected migration as the culprit behind reduction in dolphin number because the number of casualty had also dropped. Just one death had been recorded last year while the number of calves increased from 4 to 11.