I was heading out to the far back of the yard when I passed the large maple tree and a huge flock of starlings and perhaps also grackles, flew right over my head like I was in the Hitchcock movie The Birds. The bird sounds were loud and very alarming. I tried shouting and shooing with my arms. I turned around to see a large number of the black birds swooping into the big maple tree, then I saw a gray bird exit the tree clearly fleeing for its life, being attacked by the starlings in mid air. One starling violently knocked the gray bird right out of mid flight and the gray bird fell to the ground right at my feet where I stood. I bent down to look at the bird and over about 2 or 3 minutes, I watched as his breathing slowed and then stopped. In another minute, literally about another minute later, flies started buzzing around the body.
I’m not sure if this bird was a mockingbird or perhaps a catbird. I think it may have been a juvenile.