Breeding iguanas is an important step that you can consider making. But before you decide to breed your iguanas, you must learn about their behavior, breeding conditions, how to create a nest and incubate the eggs. This post will help you learn everything about breeding iguanas and caring for their eggs.
Iguana breeding season and aggression.
You probably know already that iguanas can get very aggressive towards other iguanas and even their owners during breeding season. This is completely normal, and you should take care during this season and minimize any handling.
Male iguanas become aggressive towards other males as they wish to present themselves as leaders and dominant figures in their territory. What is more, male iguanas can become aggressive towards a female owner and other female iguanas. All of this is due to higher levels of testosterone.
Neutering your iguanas before they reach sexual maturity can, to some degree, solve a problem of aggression. If you don’t plan to breed your iguanas and don’t like them being aggressive during mating seasons, neutering can be a solution.
Consult your veterinarian to discuss this. However, this can be expensive and ineffective – especially with iguanas that have already hit the puberty.
When do iguanas breed? And how can you tell it is iguana’s breeding season?
In the captivity, iguanas can breed at any time through end autumn through spring. You will be able to tell that your iguana is trying to breed when their behavior changes – males become more active and they bob their heads. They can also do pushups, and some types of male green iguanas can even change their skin color to bright orange/yellow (even females do, but not to the same extent).
Other usual signs are increased aggressiveness (or being more straightforward in what they do) and less interest in handling. Female iguanas can show some signs of aggression as well, but not very severe.
Iguana breeding age
Male iguana’s pores will have more secretion during the breeding season – you can help clean it by bathing your iguana daily and massaging the pores.
Iguanas reach sexual maturity at around 2-3 years old, so most iguanas in captivity will reach the breeding age at 2-3 years old, often the second winter in captivity.
How do iguanas breed?
Male iguanas are dominant, and they become very aggressive to mate. In the wild, few males can try to win the female for mating. The female iguana chooses her partner and they successfully mate after staying together for few weeks.
In the captivity, choose calm and healthy iguanas for mating, and try to introduce them only for breeding (if you wish to witness them mating). If a female and male have lived together before, they will also be able to breed. Reintroducing a female to male is another option.
Male iguanas can become very aggressive when mating and can injure a female when grabbing her neck. If you are breeding in captivity, try to witness this breeding and separate both iguanas if necessary.
Changes for successful iguana breeding and how to help iguanas breed.
For a successful breeding, you must make some changes in iguana’s environment and diet. Firstly, your iguanas (especially female) must be healthy and given enough calcium and D3 supplements. She will need calcium and D3 when for laying eggs.
Another thing to note is that most female iguanas eat less or refuse all food 2-5 weeks before laying her eggs. Therefore, it’s important to feed your iguanas well, especially female, before breeding season.
Most iguanas start becoming interested in breeding when days become longer (longer photoperiod), humidity higher and temperatures higher. These are natural changes in the wild, and you must try your best to mimic these conditions.
Increase the temperature in the cage gradually, provide more light vs. darkness and increase humidity in the terrarium. You can mimic the natural environment by checking outside temperatures and times of sunrise and sunset. Then, set your timer for appropriate times. Read about lighting and humidity in this post.
Present you female iguana or iguanas to your male iguana few weeks before the actual breeding. One male iguana can mate with one or even few female iguanas in turns.
Male iguana will mate with a female iguana and it can happen few times before a female refuses male (she is tired or feels it is enough). Pregnant female iguana will have a large round belly, which will empty after she lays the eggs.
How long will my female iguana be gravid (pregnant) for and how many eggs will she lay?
X-Ray of a gravid iguana
Your green iguana will be gravid (pregnant) for around 65-85 days after getting pregnant. This is gestation period and it will be different depending on humidity (higher the better) and temperature (colder, the longer). 2-5 weeks before laying eggs she will refuse food. When the time comes, female iguana will lay from 10 to 65 eggs, but the average is 40.
After the female has laid all the eggs, make sure to take her to the vet to check if she did (maximum after a week). Sometimes, iguanas cannot lay all the eggs and they get stuck in the oviducts. In this case, the operation will be necessary to remove remaining eggs.
Female iguana laying eggs without a male
Female iguana can also lay the eggs without mating with a male. Check your iguana to see if she is gravid – you should be able to see bulges from the sides of her stomach.
If you think she is pregnant – take her to vet and they will perform an X-Ray which will show how many eggs she has inside of her. This way, you will be able to know if she has laid of them successfully. But sometimes, female iguanas need a surgical removal of follicles.
Not all iguanas will lay the eggs – some iguanas will reabsorb them instead of laying. But make sure to always have the nest ready anyways.
Iguana nest preparation
Preparing a nest is a very important step for a female iguana. She will make sure to find a spot to lay here eggs before 
she does so. If she hasn’t found a spot for her eggs, she might not lay them and become egg-bound. If this happens, you will have to take your female iguana to the vet for surgical removal of eggs.
This is why it is important for you to create a space (or even few) for her to consider and choose as a nesting spot. If she doesn’t pick one spot, she will carry on looking and might pick the next one. Some female iguanas even lay the eggs in different spots. Don’t risk by creating only one spot, but better be prepared for this situation.
You will know when to prepare the nest – we have mentioned that she will start fasting 2-4 (sometimes 5) weeks before laying eggs. So, after around 2 weeks of her fasting, prepare a nesting spot (or spots) and let her see and chose it.
How to prepare a nest box for your iguana
So, how to prepare the nest for your iguana to lay the eggs? The best type of a nest would be a hideout place where she can enter to lay the eggs. This can be a large thick cardboard box with an entrance, on one side of the enclosure.
Pick any box and make the hole big enough for a female iguana to enter the nest box. You can also use some kind of plastic containers (long trash can), but choose one that is big enough for iguana to enter and sit in. Wooden chambers are also an option.
Then, you must fill the flooring of the box with the moist substrate. Make sure to add a lot of substrate as iguana will dig quite deep to lay the eggs. Don’t add any accessories, pieces of furniture or rocks – this can disturb egg-laying iguana and can make her leave the egg-laying spot. Humidity in the nesting box should be high and there should be no light inside.
You can choose moistened soil, perlite and some sphagnum moss as a substrate. You should then mix one of these types of soil with half sand. Soil + sand is a must as a substrate as iguana will dig it for laying the eggs. Use sand only for a nesting site, not in the whole vivarium.
Incubating iguana eggs after laying
Iguana’s eggs will incubate for around 60 to 90 days before hatching.
Right after iguana lays her eggs, you will have to take and place them in an incubator with a set temperature.
Your iguana will also be very thirsty after laying eggs, so make sure to offer lots of water and mist her 2-3 times a day.
Buying or making an egg incubator
To incubate iguana’s eggs, you will need an incubator. There is an egg incubator by Zoo Med, which you can get and use for incubating the eggs. This incubator has digital controllers with
display, and you can change the temperature and humidity to the levels that you need. Heating element underneath will keep the eggs warm.
But if you don’t want to buy an egg incubator, you can try to make one yourself.
So, how to make a DIY iguana egg incubator?
Try to make an egg incubator before the female lays her eggs and have it ready. Transferring just laid eggs to the incubator as soon as possible is important. Right temperature, substrate and humidity are key factors for successful egg hatching. Generally, the humidity in the incubator should be high (around 95% – moist substrate and water will provide that) and same goes to temperature – you should keep it to around 85 degrees F.
Making an egg incubator is not too hard but will require time.
We will place the eggs in the box, which will then go into the incubator. Box will only hold the eggs in the substrate, but the incubator will hold the box and have the heater and thermometer to supply the heat and check the temperature.
- Firstly, you must pick a substrate which you will use to bury eggs in. You can choose vermiculite, perlite
(or sphagnum moss as a last option). You will have to mix the medium with water to make it damp. Mix the soil with hands it to make it damp. Throughout the incubation period, come back to the incubator box and make sure that the substrate is wet – if not, add some water on the soil. - Then, you will have to choose a small plastic box (that has a lid) and fill it with the moist substrate to about 2 inches. Place all the eggs inside this egg box and cover the lid. Make some holes in the lid to let the fresh air in.
- The next step is to choose an incubator. This can be a large cooler box or any other plastic container that can fully close to keep the heat inside.
- The main idea here is that you will need to make a hole or somehow supply the heat (with heat tape or water heater) to the incubator. If you choose a cooler box, you will need to make a hole underneath and place the heater inside the box. You can also place a submersible water heater in the aquarium and place it under the egg box to supply heat and humidity.
- When you choose your incubator and set up the heating inside it, place the thermometer and preferably hygrometer to check for temperature and humidity.
- Place a platform (any kind) on top of rocks (above heating element) and then place your box with the eggs.
- Close the lid, but open it regularly to let the fresh air in. Check on eggs and make sure the temperature and humidity levels are right.
- Let the iguana babies hatch naturally and don’t worry if get stuck in the shells for a day or so.
- When hatchlings are out of the shells, transfer them to their new terrariums!
(or sphagnum moss as a last option). You will have to mix the medium with water to make it damp. Mix the soil with hands it to make it damp. Throughout the incubation period, come back to the incubator box and make sure that the substrate is wet – if not, add some water on the soil.Iguanas are truly amazing reptiles and breeding them can be very exciting. Please comment any questions that you have and tell about your experiences!
To finish this article, it is very important to remember that there are many iguanas in the rescues that are waiting to be adopted. It is a much better idea to adopt, rather than buy or breed your iguanas. This way, you will help house iguanas from rescues.