With rainbowboas, YOU DO NOT NEED TO PROBE.
You can feel the ends of the male’s hemipenes at all ages.
Just start at the vent, apply slight pressure between thumb and forefinger (one finger dorsal and one finger ventral) and slide toward the tip of the tail. If you feel two distinct little bumps (like two small pinheads deep in the tail tissue) then you have a male. If you do not feel them, then it is a possible/probable female. It might help to have your fingers wet, they will slide easier…but it is not necessary.
It is good to practice a few dozen times on snakes of different sexes. I like this method because it is non-invasive; it doesn’t put the amount of pressure needed to pop the hemipenes out; and is at least 95% accurate. My little baby snakes don’t even notice what you are doing, But if you try to pop or probe them, you are asking to get bit a lot. I am all about keeping the snakes happy and stress free. I would rather be wrong one out of every 99 snakes than to piss off all 100 of them during the sexing process.
Let me know how this works. If you ever see me at a show, I will let you practice on LOTS of little babies. I show this “trick” to everyone because it is a quick and easy way to determine sex on boas.
Best of luck,
BHH
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