What happens to the two hawks in Toni Cade Bambara's short story "Blues Ain't No Mockin Bird"? Why?

Both hawks are killed by Granddaddy Cain in Toni Cade Bambara's short story "Blues Ain't No Mockin Bird." The first is hunted by Granddaddy for dinner, whereas the second is killed to keep it from attacking. The first hawk, the female hawk, is brought home for dinner by Granddaddy, who came home from the woods with the "chicken hawk slung over his shoulder," having just hunted it. The hawk is still partially alive and dripping blood. Meanwhile, the two men still stood in Granny's flowerbed, and Granny asks Granddaddy to drive them away. Granddaddy doesn't have to, though, because the mate of the hunted chicken hawk swoops in and tries to attack anyone in sight as revenge for the death of his mate:

And then this awful thing—a giant hawk—come wailin up over the meadow, flyin low and tilted and screamin, zigzaggin through the pecan grove, breakin branches and hollerin, snappin past the clotheslines, flyin every which way, flyin into things reckless and crazy.

In his state of craziness, the hawk begins attacking the cameraman and his partner. The two ridiculous men do what they can to protect themselves by jumping around, ducking, and trying to wave it away with their caps. Granddaddy Cain rescues them by calmly throwing a hammer at the bird, which falls dead, "silent and slow." After rescuing the men from the hawk, Granddaddy demands their camera, pulls out the film, hands it back to them, and tells them to leave.