Sexing Snakes Using Probes

Sexing Snakes Using Probes

Sexing Australian Snakes Using The Cloacal Probing Method

Most Australian snakes are difficult to sex as there is often little if any observable external differences. The most common, simple and effective way of determining if a snake is male or female is to carefully use specially manufactured metal snake probes to probe the snake’s cloaca and therefore assess the sex.

Cloacal Probing
Cloacal probing involves placing a smooth and round-ended metallic probe into the cloaca of the snake and then directing it to where the hemipenes* would sit in a male. The basis of the Reptile Probing Method is that if the probe advances only a short way, then the snake is a female as there is no hemipenis for the probe to advance into.

Image thanks to J. Laszlo 1975 Probing as a practical method of sex recognition in snakes. International Zoo Yearbook 15:178-179.

*Hemipenes are a pair of intromittent organs in male snakes and lizards that are designed to deliver sperm when erect during mating, much like a human penis. Apart for mating, hemipenes are usually held inverted within the body of the snake or lizard. They are held in the body just like a finger of a glove that inverts into the hand section. Hemipenes are everted outside the body when they become erect for mating. When erect, hemipenes can look very different by species, some even have extra features decorating them such as hooks and spines. 

Warning: Incorrect probing technique can cause damage and injury to your pet snake and lizard so it is recommended that your initial probing attempts be conducted with the guidance and supervision of an experienced person such as your reptile vet. 

Snake Probing Step By Step Procedure

  1. Acquire a range of sizes of specially manufactured smooth and round-ended metallic snake sexing probes;
  2. Clean and sterilise the probes. Relatively neutral pH sterilising agents such as alcohol, boiling water, commercially available sterilising fluids, etc can be used to sterilise the probes. Bleach is a strong alkali and should not be used.
  3. It is recommended that a second person is utilised to help to hold the snake during sexing. This is to ensure that the person probing doesn’t get bitten ;
  4. Gently but securely hold the snake and move the tail so that there is easy access to the cloaca for the probe;
  5. Choose the most appropriately sized probe. Generally, the smallest probes of around 1mm (referring to the diameter of the rounded section at the end of the probe) are suitable for hatchlings and the largest sized probes around 5mm are used for large pythons. Choose the largest sized probe that will easily slide into the hemipenis of the snake if it were male. This sized probe will only allow the probe to travel a short distance if it is actually female.
  6. The round end of the probe should then be generously covered in a water-based lubricant such as KY Jelly; 
  7. Insert the snake probe very gently into the snake’s cloacal opening in a direction towards the tip of the tail;
  8. Angle the probe so that the probe is parallel to the snake’s ventral scales (i.e. parallel to the skin);
  9. Gently push the probe into the cloaca towards the tail. As the hemipenes in a male snake are on either size of the cloaca and not in the centre, it is best to probe on a slight angle so that one of the hemipenes can be located if the snake is a male. 
  10. Only ever very gently explore with the probe, forcing the probe will likely result in internal damage to your snake, a far too common injury caused by incorrect snake probing. If the probe doesn’t slide easily towards the tail then it could be a female or the probe may be too large;
  11. For male snakes, the probe should easily penetrate around half the length of the tail (which is typically past the 3rd or 4th sub-caudal scales); 
  12. For female snakes, the probe will go a much shorter distance not further than the 2nd or 3rd sub-caudal scales. Although some species reportedly can go much further including Diamond Pythons.
  13. Test the other side of the cloaca (by trying to insert into the other hemipenis) to verify your snake sexing conclusion. Some experts have observed that males are typically much more uniform in internal structure than some females, meaning that probing both sides of a male often generates consistent probe depths which is not always the case in female snakes.

Probing of Australian Lizards To Determine Sex - Sexing Lizards

Theoretically you could probe most Australian lizards to determine their sex using the same procedure as for snakes above. Although some experts describe it as being more hazardous for your pet lizard than snakes possibly due to most lizard’s typically being smaller in size than snakes. However, as Australian lizards can nearly always be successfully sexed based on differences in appearances it is recommended that you not use reptile probes to sex lizards as stress free observation alone will provide you with the lizard sexing answer.

Reptile Sexing Probe Kits Supplied By PetWave 

Determine the correct sex for any size snake – key piece of equipment in reptile husbandry.

Surgical grade stainless steel reptile sexing probes are sold in sets containing different sizes of probe. For the 6 probe set, the round polished ball tip sizes vary from 1mm to 5mm. 

The smallest reptile sexing probe of 1mm being perfect for hatchlings and juvenile snakes and the largest snake sexing probe of 5mm being ideal for large pythons. The 2mm reptile probe is probably the most popular used for small and medium sized snakes. The ball tips reduce risk of injury when probing.

Set comes in a leather case with zipper for perfect storage and protection.

Shop for premium quality snake sexing probes from PetWave today.

About PetWave

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