green iguana behavior

Question
Hi--we have a female green iguana who is in her fourth year.  About 8 weeks ago, she had a "fit" in her cage, thrashing about wildly and shoving her nose through the holes in the cage wire.  At that time, she hadn't pooped in 2 days so i really tought maybe that is a sign of pain in a reptile--that she may have had a gas pain like humans--since they can't make sounds, how do they express pain/discomfort?  That was my reasonsing.  It didn't happen again for a while.  About 3 weeks ago, this started happening about 2 times a week.  One time she had just pooped when this occurred. (she had a checkup last month and no outward problems were seen--however, i forgot to ask vet at that time about this--could it be because she is in an environment too small for her?  She is 45" long, weights 6.9 lbs and is in the largest dog cage they make--36"by about 23"--we are having a new cae made for her, 7'x6'x3'--do you think her behavior is related to pain, to being "stir crazy" in her environment or something else?  We let her free roam, but not every day.  THANKS SO MUCH>

Answer
Patricia,

In my experience with iguanas, they do not outwardly express anger at being in pain. They actually attempt to hide being in pain because in the wild, a weak iguana is easy prey, so they are notorious for not showing when they feel ill. It is possible, of course that it has something to do with an underlying health condition and this cannot be ruled out entirely unless it is evaluated by a vet, but in my experience, I do not generally feel this sounds like an underlying health condition. I do not suspect this has anything to do with her bowels either. It appears to me to be strictly a behavioral issue. She is expressing some sort of displeasure either with her living conditions or with people approaching her. Is it possible that she is not a she at all and rather that she is a he? When we observe stark changes in iguana behavior and begin to see aggression, our first thought is a male coming of age and expressing his sexual frustration.

Here is an exerpt from anapsid.org regarding breeding season basics and male frustration:

"My female is suddenly acting weird! She's five years old, and has always been pretty inactive. Suddenly, she is pacing her tank, digging at the floor and substrate. What should I do? What's wrong with her?!"

It isn't strange and sudden - it's quite predictable, accruing same time every year, once they hit sexual maturity. They should reach sexual maturity at 1.5 years of age if they have been fed and housed properly, anywhere from age 3-6 if not. The sad thing is that the only reason so many owners think that these behaviors are "strange" and "sudden" is that, to date, most igs have died before attaining sexual maturity. Now that we are getting better diet information out there and better veterinary care, igs are finally living a bit longer and attaining maturity, albeit late in still too many cases...

Iguanas need space to roam - males to 'protect' their territory, females to find nesting place. Most enclosures sold or built for igs are way too small. This results in increased aggression from increasingly frustrated males (often compounded by more than 10-12 hours/day exposure to UV A or UVA/UVB, with this supplemental lighting being kept on until late at night), and may cause injury as they bash their face against the enclosure wall, rip their toes trying to claw out, and trash their tail whipping it in such confined quarters. I find that giving most males as much time as they want in front of a mirror each day, and freedom to roam around, dragging their thighs to their heart's content, results in an uninjured, well-balanced healthy male. Yes, I still have to watch my colors with a couple of them, and it is rather cute to see them 'act like gentlemen' and stand up when I enter the room (actually, presenting to me, collapsing like puppies when I stop to pet them, as long as I keep my hand carefully away from their open mouth!). But I am always aware of what is going on, and who is in an aggressive breeding mode, and mitigate my behavior accordingly if necessary, depending on the individual."

Please spend time investigating the possibility of breeding season aggression and if your iguana could be a male afterall. If you are still worried about health-related issues, please see a veterinarian to confirm whether or not this is a contributing factor.


Thank you for your question and please follow up with any further questions.

Sincerely,

Sara J Gwerder
President
Raptor Rescue Iguana Sanctuary
Shreveport, LA
www.RaptorRescue.org

Good Diet + UVB Radiation + Proper Temperatures + Set Daily Schedule = Healthy + Happy Reptile