Around 50 white-throated laughingthrush birds died mysteriously in the forests of Berinag sub-division of Pithoragarh district in Uttarakhand.
Berinag forest range officer Manoj Sanwal confirmed the mass death, saying they were being sent for a postmortem to ascertain the cause of their death.
The birds were found dead on Tuesday, he said.
Eyewitnesses who reported the matter to forest authorities said the birds either fell dead from trees or died instantly after falling to the ground.
"There are two possibilities behind the death of the birds in such large numbers. Either the group ate pesticide smeared food thrown about by people in the forest or they died of some infectious disease," said well known bird watcher and nature lover of the area Ram Narayan.
"This is the first incident of mass death of birds in the district. It may even be the first of its kind in Uttarakhand as I have never heard of mass death of birds during my 20-year stay in the Himalayan foothills," he said.
Ram Narayan resides in Sarmoli village of Munsiyari sub division.
White-throated laughingthrushes are local species of sub Himalayan hill tracts and are mostly seen in groups of 50 to 100.
These birds are partially white and partially orange coloured below their neck.
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