Is there any evidence of blue jays preying on other birds? Are blue jays known to prey on other birds? I've found that they are known to raid nests of eggs and young, but have not found any evidence of them actually preying on other birds. Background: A few years ago while raking leaves this time of year (late Oct/early Nov) the head of a house sparrow fell on me. I looked around in the spruce tree I was under and saw a blue jay eating the rest of the house sparrow. This was approximately 10 feet from my bird feeders. I can't say that it wasn't dead beforehand, but it's proximity to the feeders made me wonder.

Yes! This article gives an account of a Blue Jay killing and consuming a Cedar Waxwing, and further it clearly states that at times Blue Jays do predate on fledgling and adult birds, and gives a hefty amount of sources to back that up, if you're in the mood for further reading.