As many as 47 peacocks were found dead on Saturday near a lake at Madurantakam in the Madurai district with poisoning suspected to be the cause of death, police said.
The carcasses, which were found by villagers, were seized and sent for post mortem, they said.
S Arumugam, Range Officer, Madurai Wildlife Range, said the birds were suspected to have been poisoned as they were eating paddy of farmers.
"Those who had poisoned the peacocks will be arrested as these birds are protected under the wild life protection act. The punishment for killing them is upto seven years of imprisonment," he said.
Police quoted forest department officials as saying they were worried about increasing threats to the existence of the the bird from poachers and farmers.
The officials said peacocks are found in large numbers in various parts of of Madurai and in water sources, including tanks, lakes and channels.
They said there had been a steep reduction in the number of peacocks at Tiruparankunram hills as it was shorn of its natural green cover, which attracted the birds.
A Raja, a villager, said the locals used to feed the peacocks rice and pulses. They grew worried when the birds did not turn up on Friday for their food, went looking for them and found them dead early this morning.
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