Hi everyone. We just got a second glider a few days ago, and he was checked by a vet and neutered before we got him. Remember he's awake at night and out and about, once in a while we'll hear him make a strange sound that's different from this "sneeze" sound they make when cleaning. It's a much louder sound that is more like clearing the sinuses. A few loud inhales and exhales in quick succession... almost like another animal might do sheen clearing a hairball. Sometimes it's once and then that's it. Other times ours one, then 30 seconds, then again. Sometimes more. But whenever we run into the room to see what he's doing, he's just normal and moving around his cage. Other than the sound, he acts pretty normal. Though he did have diarrhea two days ago when we started hearing it (related? I dunno).

Any thoughts?

Some extra details...

Each glider, my first and the new one (not yet introduced), are housed in separate cages that are next to each other.

I sat in the room for a while and watched to see what the new guy is doing while he names the noise. I saw him do it three times, while he was facing the other glider's cage and they could see each other. Is he making the along toward my other glider? He isn't being aggressive, he's just clinging to the side of the cage facing the other cage, makes the strange loud "clear throat" sound, then goes back to normal. So weird...

You may have been hearing him bark. Gliders bark like a very small dog.

Sometimes gliders will use a long Hiss sound followed by a short bark to call out to other gliders that they know are around but may be out of sight.

I'm not too sure, I've heard the sound you describe as "A few loud inhales and exhales in quick succession", and each times it seemed somehow conflictual between my female Frejya and my male Luigi over mealworms (the 2 of them are constantely competing over who controls the colony actually, but that's another topic... or maybe not).

What happens is that each time Luigi comes to get a mealworm, Frejya starts this sound, then Luigi runs at the other side of the cage and reply with the same, then if I give a worm to Luigi while Frejya doesnt have one in mouth, she runs agressively toward him and he starts running away making a sound that I can only described as high pitch complaining (or submission?).

it could just be communication, but I have the feeling that there is an agressive intone to it, especially considering how Luigi responds to it.

That being said, it never goes further than that and they never enter into open fights.

Thanks for the responses!

Our new guy does it quite a few times every night when he's awake. And now that I know he's always facing my other glider's cage when he does it, I'm less concerned about it being a health issue (which is what I thought at first). It's not a bark as Candy suggested (our more established glider barks every week or two for a few minutes, it's cute)... This sound is more like a LOUD version of their little sneezing sound when they clean. But with a bit more force to it. Maybe it is an aggressive communication sound as sjusovare detailed. As long as he's not looking unhealthy in any way, it looks like I'll find out his feelings toward my first glider this weekend when we introduce them...

So I realized the sound he's making actually IS hissing! Because I heard a little squeeky sound along with it, I didn't think it was hissing at first. He's definitely hissing loudly at the other glider's cage, but it doesn't appear to be aggressive. More like "hey you!". I hope.