Breeding iguanas in captivity is a controversial issue. As is mentioned in the article below, breeding iguanas in captivity may help limit the demand for iguanas that are imported from the wild or from iguana farms in Central and South America. On the other hand, however, breeding iguanas and selling the babies adds to an already overflowing market, and encourages low prices and the "iguanas as disposable pets" attitude that is, unfortunately, so common today. At this time, The Green Iguana Society feels that people should not breed their iguanas, for the reasons stated above. However, as always, we want to provide information to allow iguana owners to come to their own, well-informed opinions on the subject. The information below was written by Neil Sweetman. We appreciate and respect his opinions and experiences as a breeder of captive iguanas. The Green Iguana Society is grateful for his contribution.
The Pros and Cons of Captive Breeding
The Pros of Breeding Green Iguanas - Breeding iguanas is a wonderful thing to experience. The mother goes through such an expenditure of resources just to lay the eggs, that I feel they should be hatched. The mother and father recognize the babies. Iíve seen a look of wonder, especially from the mother, which is amazing. You meet a number of people who want captive bred babies. The ones that they adopt are healthy, and most survive.
The Cons of Breeding Green Iguanas - Here in the United States, iguanas are looked at as disposable pets. As a result, there are a lot of iguanas that need homes, and by breeding them you are adding to the problem. In addition, they have little monetary value, so you typically lose money when you decide to breed them.
Why I Breed Iguanas - Putting healthy iguanas of opposite sexes together is all that is needed. Since my guys are free roamers, nature takes its course. After the eggs are laid, you decide to incubate or not. Ultimately what decided it for me was that by the time the egg is laid it is two months old and it takes slightly longer than that to hatch. I feel that not incubating them is wrong. Captive breeding gives iguanas with good personalities a chance to reproduce. Those who have serious health problems are still able to produce healthy offspring. While the parents may not live full lives, their babies are able to do just that.
Getting Started and Preparing Nesting Boxes
Choosing Breeding Pairs - I tend to group the iguanas by size with one male to one or more females. The male is usually smaller than the females. This allows the females to say, "NO" with force enough to deter the male. If the female is a lot bigger than the male, she can seriously injure or kill the male. This year I put Lucy a rather large female with Herman after she finished laying her eggs. Herman spent a good part of the day trying to mate with her. When she had enough she bit his face about ripping the end front of his face off. I came home to lots of blood, and found Lucy having a bloody neck and Herman bleeding from the cuts on his face. Another case that I heard of involved a 22Ē SVL female and a much smaller male. The female killed the male. I met the female and she was adopted out of state when this happened.
No matter how well the pair gets along be prepared for injuries - everything from abscesses to cuts needing stitches. My iguanas have experienced cuts primarily on the tail, but also on arms, legs, and on the neck. While most do not require a trip to the vet, some do. One thing Iíve noticed with Mojo over the last six breeding seasons is that he has gotten very gentle with mating. I rarely see any bite marks on the females now, not even bruises. Maybe as he's got older some of the hyperness isnít there any more.
Nesting Boxes - For nesting boxes, Rubbermaid Roughnecks are the best. They hold about 200 pounds of play sand and are easy to work with. On top of this I bolt a tray planter with one end cut off. This gives the iguana a tunnel like the books say they use in the wild. The play sand is moist enough after adding water to where it will hold its shape when you squeeze it in your hand.
Media Iíve tried -
100% Potting Soil Ė The first year George laid eggs this was my choice. The biggest disadvantage was the black iguana that emerged after laying eggs. Poor George was dirty from head to tail. Also she didnít seem to like it. Until her next shed, she was filthy.
50% Potting Soil and 50% Play Sand Ė I used this the second year George laid eggs. Once again I ended up with a very filthy iguana.
100% Play Sand Ė This is the best. Iíve been using this for the last four years. It is easy for the female iguanas to dig in, allowing them to easily form a pit for the eggs. The eggs come out nice and clean, which seems to help with incubation without fungus attack.
Other Nest Boxes I've Heard About - Another option is big wooden boxes, as shown in the video with Adam Britton and Melissa Kaplan. Sand was used for the media and it had the same type of tunnel I use. There is nothing real original in mine. A plastic trash can was something I used with George the second year she laid eggs. It wasnít a bad idea, just very heavy. Also there is one iguana that used a futon to lay its eggs.
Miscellaneous Notes -
After the iguanas are done nesting you can end up with a large quantity of sand to dispose of. Deciding what to do with it can present an interesting problem.
The iguana should lay all of its eggs in a single sitting. If not, an x-ray afterwards is a good idea, as the eggs may not all be laid. Even if the iguana is extremely slim, eggs can be hiding in the rib area where they are very difficult for you to see.
My females all spend a lot of time exploring the nest boxes. They dig a lot. Often they freak me out since they will spend hours at night just digging and not lay their eggs.
Females will guard their nest boxes. Iíve had a much smaller female chase a larger female from her nest box after the eggs are laid. This behavior has been documented. One such place was at a Disneyís Wilderness Park. Sometimes they go in it days afterwards and dig around some more.
All my females lay their eggs at night.
Incubating the Eggs
The incubating of eggs involves containers, media, and of course incubators.
Containers - This year and part of last year I used the Gladware Entree containers. You get five of them for less than $2.50 and four fill an incubator. These work well and are microwavable. There are also containers made by Ziploc. However, these are smaller and donít completely fill an incubator. Iíve also used Rubbermaid containers that are about one inch tall. I think they are meant for sandwiches. These work very well also.
Media - The only media I've used is vermiculite. I've heard that perlite also works well. An important part of the media is the moisture content. In an old Reptiles magazine article, I found a 2 to 1 (vermiculite to water) by volume moisture content recommended. This works fine and usually requires no additional water. Too much water will cause the eggs to have a fungus problem. Too little water causes the eggs to collapse, which seems to slow development even after adding additional water.
Incubators - The only ones Iíve used are Little Giant Still Air Incubator model 9200. Iíve gotten all of them from a local feed store. They run about $42 with tax. Of course you will need a thermometer to set the temperature, since this is not part of the incubator. The easiest ones to use are digital (indoor/outdoor). Look for one with a small temperature probe since it makes life easier to have the display sit on top of the incubator. Testing the thermometer is important. I use a cup of ice water for this. If the thermometer is within a couple of degrees of 32º F (0º C), then I use it. This is not exact but it works as a guide. The digital thermometer Iíve liked the best are from Radio Shack and cost about $10. The main thing to look for in digital thermometer is the size of the probe. You want it small enough to fit into the holes in the top of the incubator. This minimizes the times you have to open the incubator to monitor the temperature.
Putting It All Together - Gravid female iguanas go into a mode of behavior that could be called hyperactive weeks prior to laying eggs. When I see this, I set up the incubators and adjust the temperatures. I try to get the temperature in the area of 82º to 86º F. Temperatures higher than 88º F will increase the risk of birth defects in the babies. The 82º F mark seems to produce the best offspring.
The night the female goes into the nest box and digs late, I add the vermiculite and water to the containers. After this, the container goes into the microwave for a minute and 30 seconds. After heating I leave the lid on loosely and set them on the counter until they cool down. I store them in the incubator until the eggs are laid.
The eggs are put about 3/4 of the way up in the containers. Incubation lasts anywhere from 60 days to 90 days. This year I set a personal record for the longest time at 93 days.
Care and Placement of Hatchlings
Hatching - When the eggs start to hatch, I panic. One thing to be aware of is they will hatch out over the course of about 10 days. Sometimes you will see a cut in the eggís shell. At other times, the baby iguana will cut the egg under the vermiculite. The first one to hatch usually emerges quickly and without an egg sack. Most will cut the egg shell and sleep for a while. Later the baby will poke its head out and it will sleep some more. Finally, days later, it will emerge. Usually they have a small yolk sack on them that disappears in a day or two.
Some eggs will look good but will never hatch. Opening them up usually reveals a beautiful baby iguana that for some reason failed to hatch. Other times the baby is deformed so that it could not cut the egg, or the baby will cut the egg and end up drowning.
Once the baby cuts the egg and starts to emerge, it is important to disturb it as little as possible. The baby will come out when it is ready. If the baby is disturbed too much it will emerge early with a really big yolk still attached. The baby can tear it. While Iíve had this happen, the baby grew just fine. Iíve heard this can kill the baby, but this has not been my experience.
Care of Hatchlings - Hydration is very important. Typically the first week or so that the babies are out of the shell, I get them something like Nutribac and some baby food (green beans and squash are favorites) to lick. Some have better appetites than others and will try to bite the plastic spoon I feed them from. After that I place them in the tub with about an inch of water in it. Iíll leave them in it for a half an hour or so.
This handling serves a number of purposes. First, it gets the bacteria in them they need to digest food. Second, it stimulates their appetites. Third, it helps with taming. This is the most important thing. The baby associates humans with things it enjoys, both food and swimming. I feel that this eliminates a lot of fear of people these guys have. While they are still concerned about being handled, they donít struggle like they fear for their lives.
Once their egg sacks are completely gone into a cage they go. Also around this time they are fed the same thing as the adults - MK salad and greens (mustard and turnip since they are soft). Of course you have to chop it a lot finer. I use kitchen shears for this. Also I sprinkle lots of alfalfa on their food. I made these diet changes this year and the babies are doing really well. The previous two years I fed them more baby food and kept them inside longer. This yearís babies are 14-18Ē long at four months old. They are shedding a lot and eat like pigs. Youíd be surprised how much food 20 baby iguanas can eat.
Placement of Hatchlings - Finding homes for baby iguanas is extremely difficult. Iíve found the following things helpful in finding homes. The first is networking. The first year I had babies I placed half of them with friends, neighbors, or co-workers. These are easy to track, as these are people that I see every now and then. The second is posting on the internet. The most common way I ship is something like Delta Dash. This is a means of testing potential owners. If someone is willing to spend $90 for shipping an iguana, they are likely to take good care of it. Some of the babies went to a rescue that works with disadvantaged children.
Iíve also sold a number of them at Reptile breederís expos. All came with Melissa Kaplanís Guide to Care and Socialization. Some went to a couple of vets.
Finding homes for iguanas is time consuming. Considering that in a single year you can end up with 30 or more babies per female adult iguana, youíve got to come up with ways of placing them that you can live with. Iíve even thought about getting my breederís license so I can sell them through the newspaper.
The key is to find people that you can stay in touch with. Co-workers are great because you see them every day. Unfortunately, there can be so many babies that it is difficult to track them.