Crows are predators of baby birds and nestlings when their parents are not around. They will eat eggs, nestlings, and even adult birds if they can get their hands on one. Crows are known to snatch other baby birds or eggs out of other bird's nests, and brutally eat them.
Crows will eat hatchling birds give the opportunity, especially during baby season when they have their own mouths to feed. They will occasionally prey on smaller birds like songbirds, pigeons, doves, sparrows, canaries, and finches. Once in a while, they can kill and eat larger birds such as chickens.
ttps://www.chrislehnes.com/flower-box-bird-nest-mourning-doves-nest-repair/