i don't know what kind of bird that was, but I regularly find what I refer to as "bird explosions" of feather and down in my yard - confirmed a few days ago by witnessing an attack in progress, mine are a result of feral cats making their kills, eating everything that tastes good to them, and leaving behind the feathers.
Location: Northeast - 5B
posted 3 years ago
here is the other pic
"Rather than a problem to be solved, the world is a joyful mystery to be contemplated with gladness and praise." Pope Francis
As Mr Livingston suggested a pigeon and probably a cat, buzzards don't leave the "scene of the crime" this clean or they leave nothing at all.
And there is probably a nice hiding place for the cat and a food source for the pigeon nearby if you look around.
Make yourself as serene as a flower, as a tree. And on wednesdays, as serene as this tiny ad: