Anyone else noticing this? I always save videos that "prove" something about UFO's to be a hoax and for some odd reason, those videos are being deleted from youtube. Is it because these hoaxes have some sort of copyright?
Any creative work is automatically copyright. UFO hoaxers are usually pretty fast to whack the ban hammer on anyone pointing out that they're lying.
That said, you have some recourse behind Fair Use, when evaluating and reviewing a piece of footage, or artwork. Namely, I can't show you photo of an iPad in the 19th century that someone else mocked up, but I can show a small part of it to show how one can tell that it was photoshopped.
How have these videos been deleted though? Usually, they have to do a DMCA takedown notice in order to remove any videos, at which point, you're able to file a counter-notice of non-infringement and then they can either decide to take you to court, or let the video remain up... if your videos are just disappearing with no notice of how or why, then... I can only imagine that your account was hacked...