I looked out, and sure enough, there was a blue jay with its back to me, head going sharply up and down, and the unusual sound was coming from the area of that blue jay.
(from my phone)
It just kept pecking, moving a little but, until I could see it had a sparrow underneath it, and the sound was coming from the sparrow. Then it stopped a while, and the sparrow stopped moving...must be dead.
About five minutes later, there it is still pecking away with abrupt peck...peck...peck. Odd. Strange behavior to see it pecking at a dead bird like that, then I realized it was eating it.
Well, it's dead. Can't hurt it anymore.
Then the sparrow came to life, fluttered around...and the blue jay just hopped on it again.
Peck...peck...peck...swallow...peck...swallow...peck...peck...peck.
And then the sparrow started making that sound. You know a sound you may have ignored for some time, like some kind of squeak inside a car you hear every time you go over a bump? You didn't hear it until your best friend says "Hey...you got a squeak."
Then you hear it, and you can't un-hear it anymore. That was the sound that sparrow was making as it was being slowly pecked to death and eaten alive. It became gruesome to listen to. And the more I heard it, the nastier it sounded.
I said "Screw this. I went outside and the blue jay took off after one final peck when it saw me. I saw the sparrow sitting upright, blood on its head, and both eyes pecked out as his little head quivered back and forth.
I don't have a problem with killing an animal if there is a reason, but I hate to see an animal suffer. That sparrow wasn't dead, but it already was.
I said "Sorry, guy" and brought my heel down hard, killing him. Like I said, I hate to see any animal suffer. I saw a video of a lion getting mauled by what looked like a cape buffalo (Link). That full grown male lion had definitely killed and eaten things while they were still alive, but...it was hard to have that feeling of "What goes around, comes around" when you saw him taking it.
Anyway, I intervened and helped him escape in a way. I must say, I fully expect this of any wild creature, but...a blue jay and a sparrow just seemed...well...not really the most likely players in a clear case of bird murder, or so it seemed.
I know sparrows can be aggressive, especially to each other, and I remember a flock of blue jays attacking our family lab when I was about 7 years old, so I know blue jays can be real bastards sometimes.
But I had never seen a blue jay seem to murder another bird, but....that is exactly like what it seemed to me. I know it is anthropomorphizing their behavior, but...there was something emotional in that blue jay's demeanor, not the business-like peck of a crow picking at a carcass in the road before calmly taking to the air to avoid an oncoming car.
If this blue jay was a human, it would have had a knife in its hand, with each strike at its victim saying "Take that! Take that!" It was positively vengeful.
And I swear, the way it looked at me when I came around the corner, and instead of just flying off, it turned and deliberately took one more peck before flying off, it seemed like there was...malice. Not hunger. Not boredom. It was weird.
The Internet tell me that Blue Jays are part of the Corvidae family of birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. Basically, the crow family. So I guess that behavior is very crow-like. But it was the seeming malicious intent on the part of the Blue Jay that threw me for a loop.