UFO or part of a wing separated or a feather fell from the raptor or a processing remnant.
Ah, I see you are a UFO denier! ๐
If people believe in intelligent alien life, I wonder if they have considered species that are tiny or huge. There have been very few sci-fi story lines about large and small aliens.
Small birds pester eagles a lotโฆand the eagle typically just ignores them. It can't move fast enough to catch them anyway due to the larger size/mass/momentum.