Tail Rub Method (Boas)

For snakes from new born to 4' (up to 5' on animals with less developed muscle), you can use the "rub method" place your thumb right below the vent and forefinger opposite side. Gently slide thumb and finger towards the end of the tail. You will feel nothing at all if it is a female, but about 1/3 the way down if you feel two tiny balls slide out from under your thumb - you have a male.

    Females have shorter blunter tails after the vent and smaller spurs (in general)

Males have longer, narrower tails after the vent, and larger, more hooked spurs..

  Females have smaller spurs (in general). When probing, the probe will only descend 3-5 sub-caudal scales towards the tip of the tail. Make sure to probe on both the left and the right side, in case of past damage or uneven depths.

 Males have larger spurs (in general). When probing, the probe will descend 5-8 caudal sub-scales towards the tip of the tail.