ATB sexing HELP

I recently got an ATB, I have had it since February and it’s been amazing. I love how different they are from my ball pythons. I have thought about getting another, maybe even breeding in the future. But how do you sex them?!
Obviously I cant sex them the way I would my ball pythons.
Is anyone here experienced with this and can maybe give any tips/advice


I know this is an old thread but wanted to bump as I have an ATB and Northern Emerald Tree Boa that I’d like to sex. Of course first I have to learn how to use a probe Kit (and buy one). I’m just curious as to how difficult is it to do…Thanks.


I’ll preface this by saying I’ve never sexed an ATB. My arboreal experience is from GTPs. But I imagine the basics are the same.

With GTPs I never attempted to sex before they were a year old. The young ones were too delicate and tiny. That may be different with ATBs.

I never popped arboreal snakes because of how delicate their tails are. Very different than kings/BPs/etc. So I always used a probe. You can buy probe kits from most reptile outfitters online.

2 people really helps, although once you’re proficient at it you can certainly do this by yourself. Have your partner (or your non-dominant hand) control the body of the snake. With your dominant hand, insert a lubricated (mineral oil) probe into the vent pointed towards the tail.

Slowly and gently, insert the probe until it will go no further. Use VERY minimal pressure. Stop when you feel resistance.

Use your thumb to mark the position of the probe next to the cloaca. Gently remove the probe, leaving your thumb in position. Hold the probe up next to the outside of the tail with your thumb on the probe and next to the cloaca.

Count how many tail scales (subcaudals) the probe went in. Different species vary, and I don’t know about ATBs, but females usually only probe to 3-5 subcaudals. Males probe way deeper because the whole premise of this is that the probe is going in the inside of the inverted hemipene in a male snake and there’s not a hemipene to enter in a female.

Hope this helps.


I have a probe kit i think could work. My fear as stated by you and previous commenters is how delicate they are.
I have had this individual about a year and its gotten some size but I may wait longer before attempting to sex this way.
I have read online that people we able to sex them based on features such as tail thickness and facial structure.
Thank you for this adivce! I think ultimately to know for sure i will have to probe but first ill try and reach out to anyone who may be able to help me near us.


Here’s some recent photos. Its eating great and handles wonderfully for an atb :blush:


There are ways to tell based on tail shape. Males generally have longer tales with a thicker base. But it’s really hard for an untrained eye without another individual of the opposite sex and of the same size to compare. You can get good at it though, if you see enough of a species.

Probing (or popping, for juveniles of less delicate species) is the only way for most of us to be sure.