This is a Hindu ritual performed by the Naga descendants' sects like the Bunts and Nairs, and all castes hold the Sarpa Kavu in reverence, with access forbidden to the area unless for due ceremonies.
Mythology says that Kerala was created from the Arabian Sea and given to the Brahmins (Namboothiris) as a "donation" by Parasurama to save himself from the sins of killing numerous Kshathriya kings.
The Brahmins also worshipped Anantha and Vasuki and the pleased snake gods made Kerala suitable for living.
[1] Sarpa Kavus even help in soil and water conservation besides preserving its rich biological wealth.
The nutrients generated thus are not only recycled within the sacred grove ecosystem but also find their way into the adjoining agro-eco systems.