Known as 'sarpakavu' or 'kavu' in local parlance, sacred groves are traditional places of worship with some of them having idols of snakes and goddesses.
The increase in number of construction of new buildings in the place of ancestral homes, which used to house sacred groves in its premises, have virtually led to the destruction of this biodiversity system, a recent report by state Assembly Committee on Forest, Environment and Tourism said.
"Groves are home to a large number of rare flora and fauna, including those facing extinction threat. As many as 475 species of birds, 100 species of mammals, 156 species of reptiles, 91 species of amphibians, 196 species of fishes and 150 varieties of butterflies can be seen in the groves in the state," it said.
The report, prepared by the Committee chaired by state Minister for Forest, Sports and Cinema Thiruvanchur Radhakrishnan, had been tabled in the ongoing Assembly session on March 10.
Coastal district Alappuzha has the highest number of groves, while high-range districts of Idukki and Wayanad have the lowest number, it said.
"Iringorkavu", spread over 2.5 acres in Perumbavur in Ernakulam district, is the largest grove in the state, it said.