Aftermath of Raptor Butchering a Prey Bird

I found the aftermath of a successful hunt by a predator in the windbreaker forest of Japanese red-cedar (Cryptomeria japonica, family Cupressaceae) around the farmland. Numerous blackish feathers and downs had been plucked out and scattered across the forest floor. But no carcass of the prey (unidentified blackish bird) was found nearby. I could exclude the possibility of a mammalian predator because the shaft of the plucked feather were undamaged. I suspect that an Ural owl (Strix uralensis, family Strigidae) was most likely to be the culprit. (18 Days later, I spotted an Ural owl in the daytime flying away from a side branch of a Japanese cedar, the perch was just over the plucking site.) Captured in the sunny afternoon of late-October 2024 in Japan. For a full story (text in Japanese); https://sigma-nature-vlog.blogspot.com/2026/02/blog-post_24.html