Sivasankaran

Respected sirs, Shankar from Mumbai..... Regarding Mahalaya Amavasya.... I ask a question. I put three handfuls of cooked rice every day without fail... one for the pitru vargham, one for my maternal side vargam and one for any one whom we have forgotten. This is religiously eaten by crows daily. In such a case, is it necessary to have Mahalaya Amavasya tarpanam done separately. Regards Shankar