Breathing Loudly

One time my BP was curled up with her head tucked underneath her body in her cage and started to make this loud breathing sound when I took off the top. She stopped after I picked her up. She's only done it that one time. She's a healthy snake, but I wanted to get some ideas behind it.

Sounds like she was trying to warn you off. My big male does this. He'll hiss and thump if I surprise him

Yeah it's probably just hissing. I wouldn't worry about it unless it becomes constant.

That was probably it. She didn't see me coming so it makes sense.

My spider does this all the time. She likes her space and does not like it when I interrupt her to clean her tub or feed her. Silly girl. But I agree with the others, she was probably hissing. The first time I heard my spider hiss I thought it was heavy breathing too.