The birds were found dead at Borbeel in Bagori range on November 28 last.
"We are concerned at the death of the winged creatures who are annual visitors to the park from other places in Assam and north India. A probe has been ordered", Assam chief conservator of forest and director KNP N K Vasu told PTI.
"The Centre for Wildlife Rehabilitation and Conservation (CWRC) and the state veterinary department were called. Samples were collected and they would soon submit a report", he said.
Initial reports suggested it could be a result of poisoning but later findings ruled it out. "So we called experts from the North Eastern Regional Disease Diagnostic Laboratory for a probe and the report is expected soon", Vasu said.
Samples were collected and a team headed by deputy director of the state veterinary department and his team had reached the spot the next day for verification, he said.
"We observed the behaviour of fishes and pelicans inside the park and found no change. There was also a possibility of avian influenza but that was also ruled out", the director said.
All the 152 forest camps inside the 840 sq km park were asked to report about about any death of avians but after that date nothing was reported, he said.
The National Park has been in the news this year for poaching of the highly endangered one-horned rhinos.
Apart from housing nearly 2200 one horned rhinos, the highest in the world, the KNP also has a pelican park of migratory birds who annually visit the park from various parts of the world, including Russia. MORE
