Why are crows considered important during Ashtami Shradh?

Crows are considered messengers of the Pitru Loka (ancestral realm) in Hindu tradition. Before the Brahmin bhoj on any Shradh day including Ashtami, food is first offered to crows. If a crow comes and eats the offering, it is considered a sign that the ancestors have accepted the Shradh. The Garuda Purana and Vayu Purana describe crows as carriers between the world of the living and the departed. This practice of offering food to crows (Kak Bali) is an integral part of every Pitrupaksha Shradh ceremony.