How to Tell Male & Female Fire-Bellied Newts

Wait until the newts are mature enough for breeding. Baby or juvenile newts are difficult, if not impossible, to sex without using a probe, which is not recommended for amateurs because this may injure or kill the newt. Waiting, however, can be frustrating, especially if you find out later that you have three females or three males but not a combination of the two genders. It's best to either buy the newts ready for breeding or in sufficient numbers to ensure a fair gender mix.

Examine the cloaca of the mature fire-bellied newt. The cloaca is the vent where waste is expelled from the animal. A male newt will have swollen tissues at each side of his vent. A female's vent will not be swollen and should be smooth on each side. If by some chance you have a female that has already begun producing eggs, she may be swollen with eggs close to but not at the vent area. These newts do not reproduce via insertion of the male organ into the female organ. The male deposits spermatophores onto a hard surface of the holding tank. He guides the female to one of these deposits where she takes the sperm into her cloaca.

Inspect the tail fins of the newt. The male will usually have higher tail fins with a slight blue coloration on the sides, which will not be found in females. This is usually, but not always, the case so there may be a variation of the fire-bellied species that could nullify this sexing method. Fire-bellied newts will have distinct skin textures and colors, which would account for some males with a smaller tail fin or females with coloration in their tails.