Tiger salamander oddity

[Nikki Dee]

I've noticed for a couple months now that my tiger salamander has had this odd sweeping near the base of his tail. I had thought it was simply the fact that he was male and it was his cloaca but it seems to be a rather permanent thing. Is that normal? I thought it was only supposed to be like that only like once a year?
I've attached some pictures.

 

[bellabelloo]

He looks like a normal male