Hello! I have a male Burmese python that I have been working on building trust with for the past year and a half. It has been wonderful seeing how far he has come! From loud hissing and writhing, sometimes striking, into long, curious tongue flicks and not struggling to escape. However, even once he is out of his enclosure, as I am holding him he will occasionally hiss. It’s not loud, nor is it accompanied by defensive behavior, but it made me realize that the way he ‘communicates’ is perhaps more complex than I had thought. So, I have a question for those who are more experienced with burmese pythons than I am. What kind of body language have you noticed with them? What are signs of a comfortable snake? What are some things to watch out for in a scared snake? I would love to hear all about your experiences and what you have to offer!
Sometimes with snakes, and especially one as heavy bodied as a burm, when lifting up the front third you can actually put enough pressure under them and on the lungs to cause them to hiss.
Otherwise, each snake can have their own personality, so knowing your own animal’s behavior is key. Already knowing enough of it to tell the curious flicks from the hungry licks is good. I have one adult Royal who is super defensive and I don’t let anyone else handle because she will go from balled to immediately launching at any bodypart she can see.
I know with retics, handlers have said they’ll sometimes wrap their tails tightly around a limb and do a little head tilt. That’s the warning for an incoming snap. I haven’t personally seen a burm do the same, but any mid to tail muscle bunching is probably a real good sign they’re gonna consider going for that strike.
@armiyana has nailed your question! So right, and you will come to recognize your particular snakes body language, sounds like you have come along way already, congratulations on that for sure! I really just wanted to add that Burmese are notorious for almost always hissing, not aggressively just vocal snakes in general. I had one, handled and seen more then a few that almost continuously do little hisses, or even long hisses, but nothing else. Of course not all are like this and I or anyone else can’t be certain in your case, but yours could be just a nice, friendly, hissing snake! 
