Wow, I am floored! I thought for sure the gecko experts here would know.
?????????
I thought this was a normal thing for geckos, and that I was just not "in the know". Huh? I wish I could send you both a sample of the odor, as it is VERY REAL, LOL. I've even brought my Dad into the room when he does it, and my Dad is like, "Ewww! Open the windows to air this place out. It stinks in here!", which obviously isn't something I can do during the winter. So you know, it's not excrement, as I keep his tank super clean, and remove droppings if needed (I check his tank several times a day). But no, this smell ONLY rears itself when he's stressed by two things. 1.) if I go into his room (he's in the storage bedroom next to mine) and go rummaging around and making too much noise for too long, the smell slams me, and it's like someone released "fart spray", only it doesn't smell like farts it smells like, well, almost like gecko excrement, but there's no poop to be found anywhere. 2.) The only other time he does this is if I leave his light on in his room, which is ALWAYS off unless I'm in the room. What do I mean? If I walk into his room right now, turn the ceiling light on, and leave the room for for too long with that light on, I'll come back and the entire room stinks. I'm TOTALLY serious! These are the two things that elicit this "smell". Weird, huh? Whatever it is it's VERY REAL. I just wish I knew which part of his body is emitting the smell. I even picked him up once and was sniffing him to try and figure out what part of his body it was coming from, LOL.
I assumed this was some kind of defense mechanism that maybe they use in the wild to keep other animals away from them, as who'd want to deal with an emitting horrible stench. Do we know if they have "musk" glands?
I guess I only have one other question then.
Do geckos pass gas?
Lastly, it's almost as if he's saying "this is my territory, and this is how I mark it, so I'm letting you know".