Animals are sacrificed as part of the Hindu festival, with the hope that the sacrifice will lead to the fulfillment of wishes by the goddess. It is estimated that more than 250,000 animals were killed during the period of sacrifice in 2009 while 5 million people visited Gadhimai during the festival. This centuries-old tradition is observed every five years in Gadhimai premises located in the village of Bariyapur of Bara District of Nepal near the border with India.
Male domestic Asian water buffaloes (Bubalus bubalis)(locally called "PaaDa") are the preferred species to offer to the goddess. Several other species including male goats (Boka), chickens (Murgha), Pigeons (Parewa), Ducks (Batakh) and some rats (Moos), are also killed.
Several animal-rights activists protest against this event before and during every Gadhimai festival. The 2009 event drew the attention of celebrities like Maneka Gandhi and Brigitte Bardot, who raised their voices against the killings. Nepal government officials say they cannot stop the centuries-old tradition, despite opposition from animal-rights activists from Nepal and India. Animal rights activists say they are not looking for the practice to end overnight.