This Disappears When Logged In

Iguana Breeding Season Aggression

Information Explaining Breeding Season Aggression

Breeding Aggression

Aggressive iguanas can be a handful. This is especially true for the novice owner who has never experienced an aggressive iguana before. Hopefully the information on this page will help you understand why your iguana is being aggressive and what you can do to help dissuade it of this type of behavior.

Understanding The Aggression

An iguana doesn't need to be in season to be aggressive. Some iguanas, both male and female, can be aggressive toward their owners. This can happen for many reasons but is typically a response to how you reacted when they tried to establish dominance as the alpha iguana in the household. During breeding season males tend to amp up the aggressive behavior and become very territorial and this leads toward additional aggressive tendencies. They are not trying to hurt you or your family members because of who you are. What they are doing is defending what they perceive as their territory for any potential mates that may come along. You and all other invaders are perceived as a threat to their alpha status and they are willing to defend that status.

Orange Iguana

Aggressive Triggers

Your favorite sweater could be your iguanas worst enemy. During breeding season, and sometimes outside of season, iguanas will become aggressive based on the colors you are wearing. Some iguanas tend to have a negative reaction to certain colors, such as varying shades of green and blue. (These are example colors. Your iguana may react to other colors or may have no color triggers at all. That is for you to determine based on your iguanas behavior.) Another trigger could be if you are menstruating. Iguanas have a sensitive olfactory sense organ (the Jacobsen's Organ) which can detect the hormonal changes and scents associated with menstruating. Sudden jerky movements can cause an aggressive iguana to react as if you were attacking it. Certain perfumes and shampoos can trigger a negative response as well.

Each iguana is different and each iguana is going to interact with its owner differently. Some of these triggers may be familiar to you and you may be aware of other triggers not listed. It is vital that you learn what makes your iguana tick so that you can avoid an injury to yourself and possibly your iguana.

Calming The Beast

Calming a hormone driven iguana isn't easy. Typically this behavior will only last 3-4 months (It can last much longer. Three- 4 months is an average season.) and many people just ride it out knowing there is a light at the end of the tunnel. Some people aren't that patient and they want their friendly iguana back as soon as possible. This information will help you on your conquest to calming the beast.

The first thing that everyone needs to remember when dealing with an iguana in breeding mode is that he is not simply challenging you to establish dominance. He is completely prepared to do battle with you over what he believes is you trying to invade his space and take his alpha status away. Since the iguana is hormone driven, he is very unpredictable.

Standing your ground is not always the best course of action and is something you are going to have to decide upon for yourself. A charging iguana with the intent to bite can sometimes be stopped by simply yelling at it. You will need to be very vocal and loud. You want to startle him and let him know you are in charge. Yelling "NO! Stop right there!" is sometimes enough to stop them. You would then need to immediately reinforce your status as the alpha male (or female) by picking the iguana up and placing him in his enclosure or in another room. The idea is to remove the confidence from the iguana and let him know that you control his actions. This comes with some risk however. Since your iguana is hormone driven and unpredictable you could very well be attacked and bitten. You know your iguana better than anyone and you should use that intel to decide what the best tactics are for you to deal with your iguanas aggressive behavior.

Iguanas in season are territorial. They have decided that either their enclosure or a section of your home, for those that are free roaming, is their domain and they are willing to defend it at all costs. So how does one break an iguana from this behavior? In theory it's simple, you remove the iguana from his domain and place him in your domain. If you want to remove the territorial behavior from the iguana you need to remove the territory it is defending. That means you will need to confuse the iguana and make him feel less confident by changing his habitat. Place the iguana in a room that is completely unfamiliar to him. Completely alter the appearance of his enclosure if you need to. You simply need to remove the iguanas confidence by altering what he had marked as his. The iguana will need to acclimate to his new surroundings. This acclimation period (1-3 weeks) can sometimes be enough to break them from their breeding aggression and end their season early. This won't work on every iguana.

Lighting also plays a role in the breeding season and can also play a role in ending it early. This works especially well with iguana who are residing in an enclosure since it is easier to control the light they see. If you currently run your lighting for a photoperiod of 12 hours of light and 12 hours of darkness, you will need to change it. You should decrease the lighting by 2 hours each week for 2 weeks. This will shorten the days and help convince your iguana of a change in seasons. This isn't fool proof and doesn't work all of the time. After the lighting schedule has gone down to 8 hours of light, sustain this for 2 weeks and then go directly back to the 12 hour photoperiod.

If your lighting plays a critical role in your heating you will need to use non-light-emitting items such as ceramic heat emitters and radiant heat panels for supplemental heat.

"If your iguana is super aggressive, try keeping him in a darkened room for a couple of days. Provide the necessary heat and thermal gradient but don't turn on the UVB fluorescent or the white daytime light. The objective is to trick his hormones into thinking that the season is over." [1]

Remember: Knowing the difference between an iguana testing his dominance and one that is in breeding season can be the difference between the iguana backing down when you stand your ground and becoming the victim of a full on assault by a hormone charged iguana.

Love Puppet - Sock Monster

Your iguana just wants to mate, so why not let him? Your iguana doesn't have to take out his aggression on you. You could provide him with an artificial "playmate" that will allow him to expel his aggression and will simulate breeding for him. I am referring to a love puppet, luv sock, love sock, or as I like to call it; a sock monster. As noted above, some iguanas will go after certain items based on color. If you create a fake iguana our of socks, or supply one in the form of a stuffed animal, there is a good chance that your iguana will use it to "stimulate" itself and vent some of the aggression. Your iguana will most likely attack it and possibly mount it, holding it by the "neck" as if it were another iguana. Sock monsters are pretty easy to make and most people have the items to create one around their home.

You can learn how to make a sock monster on our Creating a Love Puppet - Sock Monster page.

Green Iguana

Avoidance - Stay Safe

Very large males can be a handful for even the experienced keeper during breeding season. If your male is intimidating to you and you do not feel comfortable trying to break his routine, simply don't. There is no reason for you to put yourself in harms way. Your iguana will eventually get past his breeding season. All you need to do is limit your interaction with him during this time by simply meeting his needs of feeding, watering and cleaning. Once he is past his aggression you can resume normal interactions.

Iguana Bite Wounds

An iguana that is not given his or her space, as well as the respect they deserve, can become an injury inducing machine within seconds. During breeding season the territorial aggression is most prominent but as Lacey has shown us, you should never let your guard down when dealing with these beautiful animals.

Learn more here: Iguana Bite Wounds


Author: Richard Brooks
1. Kaplan, Melissa. Iguanas For Dummies. Hungry Minds, 2000. (pg.254)
2. Hatfield III, James W.. Green Iguana The Ultimate Owners Manual. Dunthorpe Press, 2000.
Full Orange Iguana © Cary Bass [CC-BY-SA-2.5]
Partial Orange Iguana © Daniel Schwen [CC-BY-SA-4.0]