Breeding Leopard Geckos (Eublepharis macularius) at Home: Determining the Sex of Your Pets
The ever popular leopard gecko is a good choice as an introduction to the breeding of lizards in captivity. Success, while not assured, is common…yet, these little fellows are so captivating that even zoos and well-experienced breeders continue to work with them.
Leopard geckos are often brought into breeding readiness by the slight changes in temperature and day length that are evident even indoors. With the imminent arrival of spring (writing from southern NY I am happy to report hearing a song sparrow singing for the first time today!), I thought it a good time to discuss how female from male leopard geckos differ in appearance.
Take a look at your pet’s vent, which is an opening, used for copulation and defecation, at the base of the lizard’s tail. Directly above the vent, between the rear legs, you will see a series of “V” shaped little bumps, which are known as pre-anal pores. These are large and readily visible in males and tiny and less-evident in females. The pores produce waxy secretions that are used by males to mark territories and, possibly, to attract females.
Between the vent and the base of the tail, mature male geckos exhibit a pair of bulges. These bulges conceal the hemipenes, which are used during copulation to achieve internal fertilization. Male lizards and snakes have 2 hemipenes, and can use either, but only one at a time, when mating.
You may need to look at a number of geckos, or reliable photographs, before being able to reliably distinguish males from females…but once you get the right “search image” the process becomes quite easy. Please remember that only mature animals – males of age 1 year or more, females generally of age 18 months or so – will exhibit noticeable sexual dimorphism (differences in appearance).
Please check out the book I’ve written on leopard gecko care and natural history at http://www.thatpetplace.com/pet/prod/240453/product.web.