So, you’re thinking about breeding leopard geckos? It’s an exciting step beyond just keeping them as pets, but it requires careful planning, preparation, and commitment. It’s not something to rush into. Breeding involves understanding the needs of both the adults and the potential offspring, ensuring everyone stays healthy throughout the process. This guide will walk you through the essential steps, from getting your geckos ready to seeing those tiny eggs hatch.
Getting Started: Are Your Geckos Ready?
Before you even think about putting a male and female together, you need to make sure they are physically prepared for the demands of breeding. This is probably the most crucial step for ensuring the health of your female gecko and the viability of the eggs.
Age and Weight: The Non-Negotiables
Leopard geckos reach sexual maturity relatively young, sometimes around 6-8 months. However, breeding them this early, especially females, is strongly discouraged. A female needs ample time to grow and develop strong calcium reserves before producing eggs.
- Females: Should be at least one year old, ideally closer to 18 months. More importantly, they need to have reached a healthy adult weight. A minimum weight of 50 grams is often cited, but 55-60 grams is a safer target. Breeding an underweight female can severely deplete her resources, leading to health problems like Metabolic Bone Disease (MBD) and egg-binding, which can be fatal.
- Males: Can typically breed a bit younger, around 9-10 months old, provided they are a healthy weight (usually 45-50 grams minimum) and showing breeding behaviors. However, waiting until they are a year old is generally recommended.
Never guess weights. A digital kitchen scale that measures in grams is an essential tool for any potential breeder. Regular weighing helps monitor their condition before, during, and after the breeding season.
Health Check: Only Breed Healthy Geckos
Visually inspect your geckos. Are they active and alert? Are their eyes clear? Do they have good body condition (a nice, plump tail is a good indicator)? Check for any signs of illness, parasites (internal or external), or MBD (kinked tail, deformed limbs, weak jaw). Breeding puts stress on a gecko’s system; starting with underlying health issues is asking for trouble. If you have any doubts about their health, consult with a reptile veterinarian before proceeding.
Never breed unhealthy geckos. Attempting to breed geckos that are underweight, sick, or have genetic defects risks the health of the parents and can lead to weak or deformed offspring. Responsible breeding prioritizes the well-being of the animals above all else.
Brumation (Cooling Period): Encouraging the Cycle
While not strictly mandatory for breeding to occur, many breeders find that mimicking a natural winter cool-down period, known as brumation, can help synchronize breeding cycles and improve success rates. This typically involves gradually lowering the temperatures in their enclosures for 6-8 weeks during the winter months (e.g., November to January in the Northern Hemisphere).
During brumation:
- Reduce the warm spot temperature gradually down to around 70-75°F (21-24°C).
- Nighttime temperatures can drop into the mid-60s°F (around 18°C).
- Reduce feeding frequency significantly (maybe once every 1-2 weeks) as their metabolism slows. Ensure they have defecated their last meal before fully cooling.
- Always provide fresh water.
- Keep handling to a minimum.
After the cooling period, gradually increase temperatures and feeding back to normal levels over a couple of weeks. This simulates spring and often triggers breeding responses.
The Introduction: Pairing Your Geckos
Once your geckos are healthy, of appropriate age and weight, and (optionally) have gone through brumation, it’s time for introductions. Leopard geckos are solitary animals, so introductions must be carefully managed and supervised.
Setting the Scene
The standard practice is to introduce the female into the male’s enclosure. This is because males are territorial, and placing him in her territory might make him more defensive than amorous. Ensure the male’s enclosure is clean and has adequate space.
Observation is Key
Stay and watch! Don’t just put the female in and walk away. The male will likely notice the female quickly. Typical courtship behavior involves the male approaching the female, possibly vibrating or rattling his tail rapidly, and gently nipping at her tail base or neck area. If the female is receptive, she will usually stand still and allow him to mount. If she is not receptive, she might run away, vocalize (chirp or “bark”), or bite back.
Mating itself (copulation) usually lasts only a few minutes. The male will position himself alongside the female, curve his tail base under hers to align their vents, and insert one of his hemipenes.
Separation After Mating
Once you have observed a successful mating (or if significant aggression occurs), it’s best to separate the pair. Leaving them together unsupervised for extended periods can lead to stress, injury (especially for the female), and unnecessary weight loss if the male constantly pesters her. Some breeders leave pairs together for a few days, while others separate immediately after witnessing copulation. Monitor them closely if you choose to leave them together briefly.
You might reintroduce them a few times over a couple of weeks to ensure successful fertilization, but always supervise and separate afterward.
Egg Development and Laying
After successful mating, the female will begin developing eggs. This process requires a significant amount of calcium and energy.
Signs of a Gravid Female
A female carrying eggs is called “gravid.” You can often see the developing eggs (usually two, one on each side) through the thin skin of her belly about 2-3 weeks after mating. They will look like small, oval shapes, often slightly pinkish or white. She will also likely gain weight and appear noticeably plumper in the abdomen. Her appetite might increase initially but often decreases shortly before she is ready to lay.
The Importance of the Lay Box
Providing a suitable place for the female to lay her eggs is absolutely critical. Without a proper lay box, she might retain her eggs (dystocia or egg-binding), which is a life-threatening emergency. The lay box should be a humid hide filled with a substrate she can easily dig in.
- Container: A plastic food container (like Tupperware or a deli cup) with an entrance hole cut in the lid or side works perfectly. It should be large enough for her to enter and turn around comfortably. Opaque containers are generally preferred.
- Substrate: Suitable options include slightly damp sphagnum moss, coco fiber, peat moss, or vermiculite. The substrate needs to be moist enough to hold its shape when squeezed but not soaking wet. This humidity encourages her to lay there and helps keep the eggs from drying out immediately.
Place the lay box in a quiet area of her enclosure, often partially on the warm side but not directly over the main heat source. You might notice her spending more time in the lay box and digging around as laying time approaches.
Egg Laying and Clutches
Females typically lay their first clutch of eggs (usually two) about 3-5 weeks after mating. They can retain sperm and may lay multiple clutches (anywhere from 2 to 8 or even more) from one pairing session, typically laying a new clutch every 2-4 weeks throughout the breeding season. Ensure she has constant access to calcium (a dish of pure calcium without D3) and is well-fed with properly gut-loaded and supplemented insects to replenish her reserves between clutches.
Incubating the Precious Eggs
Once the female has laid her eggs in the lay box, the next phase begins: incubation.
Handling and Moving Eggs
Carefully remove the eggs from the lay box. Leopard gecko eggs are soft-shelled initially but harden slightly after being laid. Handle them gently. Crucially, do not rotate the eggs. Unlike bird eggs, reptile embryos attach to the side of the shell shortly after laying. Rotating the egg can detach or damage the embryo. Mark the top of the egg lightly with a non-toxic marker (like a pencil, very gently) to help you maintain their orientation.
Setting Up the Incubator
You don’t necessarily need a fancy commercial incubator, though they offer precise temperature control. A simple setup can be made using a polystyrene box or a plastic container with a heat source (like heat tape or a heat mat regulated by a thermostat). The eggs themselves should be placed inside smaller containers (like deli cups) half-filled with an incubation medium.
- Incubation Medium: Perlite or vermiculite are common choices. Mix the medium with water (by weight, typically a 1:0.8 ratio of medium to water, e.g., 100g perlite to 80g water) until it clumps when squeezed but releases no dripping water. Make small indentations in the medium and gently place the eggs inside, burying them about halfway.
- Egg Container: Place the prepared deli cups with eggs inside the larger incubator container. You can put lids on the deli cups (with a few small air holes) or leave them off if the main incubator maintains high humidity.
Temperature, Humidity, and Sex Determination
Leopard geckos exhibit Temperature-Dependent Sex Determination (TSD). The incubation temperature dictates the sex of the hatchlings.
- Lower temperatures (approx. 80-83°F / 26.5-28.5°C): Tend to produce mostly females.
- Mid-range temperatures (approx. 84-86°F / 29-30°C): Tend to produce a mix of males and females.
- Higher temperatures (approx. 87-90°F / 30.5-32°C): Tend to produce mostly males.
Temperatures above 92°F (33°C) can be lethal or cause developmental issues. Stable temperatures are key, so using a reliable thermostat connected to your heat source is essential. Humidity inside the egg containers should be kept high (around 80-90%) to prevent the eggs from drying out. The moist incubation medium usually achieves this, especially if the containers have lids with small air holes.
Temperature control is vital for successful incubation and sex determination. Use a reliable thermometer with a probe inside the incubator near the egg level, not just relying on the thermostat setting. Consistent temperatures within the desired range for TSD are crucial for healthy development and predictable sex ratios.
Incubation Time
The incubation period depends heavily on temperature. Lower temperatures result in longer incubation times, while higher temperatures lead to faster hatching. Generally, expect eggs to hatch anywhere from 35 days (at higher temps) to 65 days or more (at lower temps).
Hatching and Beyond
Seeing the eggs “sweat” (develop condensation) is often a sign hatching is imminent. The hatchling will use an egg tooth to slit the leathery shell and emerge. Don’t intervene unless the hatchling seems truly stuck for many hours, and even then, proceed with extreme caution.
Once hatched, leave the gecko in the incubator container for a few hours (up to 12-24) to absorb any remaining yolk sac. Then, move it to a simple hatchling setup – usually a small container or tub lined with paper towels, a small hide, a water dish, and a calcium dish. Offer the first meal (tiny crickets or roaches) after its first shed, which usually occurs within 3-5 days. Raising hatchlings requires diligent care, frequent small meals, and careful monitoring, but that’s a topic for another detailed guide!
Breeding leopard geckos is a rewarding experience when done responsibly. It requires patience, research, and a commitment to the health and welfare of the animals. Good luck!
