Melissa Kaplan's
Herp Care Collection
Last updated January 1, 2014

Picky Eaters

©1996 Melissa Kaplan


I read posts and get email and phone calls almost daily from people whose iguanas refuse to eat certain foods. Most are from people who are trying to get their iguanas to eat a proper diet, such as my iguana salad, for the first time.


First, let me say that iguanas, like humans, do have food preferences. And, like humans, these preferences change over time. I remember the time when I couldn't stand artichoke hearts or broccoli. My mother rued the day when my taste changed and I started eating the artichoke heart - she used to get hers and mine!

I had an iguana, Dexter, who alternately loved, then hated, cantaloupe. During his love-times, he ate it daily; during his hate-times, which seemed to happen from one day to the next, he refused to touch it. This goes back to the days when I served little piles of separate foods. I decided one day to mix the cantaloupe up into the rest of the salad veggies, and that's when I realized that if everything was prepared very small and mixed together, they couldn't pick at their food, eating this, leaving that. Further research showed that finely preparing the food served another purpose: it made it possible for the lizard to actually ingest more food, and much easier for their gut to break it down and extract more nutrients.

Now, I get in 15-20+ iguanas a year. Almost without exception, each of them has a food preference/avoidance reported by their owner...hates mustard, hates parsley, will only eat dog food, will only eat monkey biscuits, hates carrots, will only eat grapes... I just smile and nod, knowing all the while that within a matter of weeks, their iguana will be chowing down on whatever I put down, even if it includes the detested food item or doesn't include the "only food he'll eat" item.

Some food preferences can easily and safely be accommodated. Doesn't like carrots? No problem - there are several different types of squash that can be used instead. But food preferences, such as "will only eat fruit and a few greens" cannot be allowed to continue as it is not a diet which provides what the ig needs.

Preferences for Harmful Foods
Preferred diets which include "he'll only eat it if it has dog food/monkey chow/eggs/chicken/etc." In it must be altered - there is no accommodation for animal protein in an herbivorous lizard diet. There is no known "safe" level, so the only safe level is to feed absolutely none. We are already putting our iguanas at risk by not being able to feed them the plants they evolved, over the past tens of millions of years, to eat and thrive upon. To me, and many reptile vets out there who see a distressingly high number of kidney failure cases each year attributed to even small amounts of animal protein, feeding any animal protein just doesn't make sense.

The "Animals Know Best" Fallacy
Too many people fall into the "animals instinctively know what's good for them" trap which, unfortunately, is responsible for the death of an obscenely high number of animals a year. Yes, an animal in its native habitat does know what's good for it. Plop it down in an alien environment hundreds or thousands of miles away, offer it foodstuffs which bear only the faintest resemblance to foods in their native habitats, and what you get generally ain't very healthy consumption preferences! Using this "they know what's good for them" rationale, I should be ripping up my floral area rug and feeding them the green leaves from it, and my favorite rainforest treefrog T-shirt - all the iguana like to try to chew on the pretty leaves and flowers silk-screened on it. I could just cut up my favorite leather sandals and feed that to my tortoises who always amble over and try to munch the straps. Azalea bushes? Oleander? With the above logic, this means I shouldn't try to stop my iguana from eating them, nor get veterinary help when he starts to have seizures and die - it's only natural, right?

What's scary here is that I have seen mail and posts from vet and pre-vet students who propound this point of view. If they don't get disabused of this grossly mistaken notion by the time they start practicing veterinary medicine, they will be just as lethal to animals out there as is the pet trade.


What to do
Follow the feeding guidelines, including recipe, time of day, being consistent, discussed in my Iguana: Care, Feeding, and Socialization document. Be consistent in where you place the food in the tank every day (in the cool side), and in the plate/jarlid/bowl that you use. Make sure the enclosure is properly lighted with white light and your UVB producing fluorescent or sunlight. Iguanas can see into the ultraviolet range; on top of their already enhanced color perception vision (much better than humans), UVA helps them to see colors even better. This makes food look more attractive and the wavelengths or light intensity (brightness) may also stimulate hormonal changes that increase appetite.

Do this day after day. Be consistent. Don't change ingredients every day or so, trying to tempt the iguana. All this says to the iguana is "if I wait long enough, this stupid human will eventually give me what I want...then we'll know who's boss!". 

So, you reach the breaking point...

If you can't stand it, or the ig is seriously stubborn, there are a few things you can do without seriously compromising your position and without reverting back to a lousy or dangerous diet. I define stubborn as 3-4 weeks of no eating. Keep something in mind - if you are seeing feces, the ig is eating something though you may not see much reduction in the amount of food on the plate!

You can gradually wean him off the bad and onto the good by using both the bad and good in shifting proportions: more bad/less good changing to less bad/more good until you phase out the bad all together. This is not something which should take months to accomplish - within a month the ig should be freely feeding on the new, proper food. This is another reason for processing the foods down to fine shreds or mince, not diced and sliced...the smaller it is, the harder it is to pick anything out (though I did once have an adult Akita who would leave three lentils and a carrot slice in the bottom of her 2 qt licked-clean food dish...)

If you are trying to get him to accept one of the ingredients in the salad, start off adding a small amount of it to the rest of the ingredients, and gradually work up. Keep in mind that different brands of alfalfa pellets and even reptile multivitamins will have different smells due to different ingredients, and sometimes those odors can be extremely off-putting to a reptile who has an extremely well-developed olfactory system. Try switching to another brand if there continues to be resistance after a month.

The Story of Iguanita...
Last year, I took in an iguana parents I had known for a couple of years. I kept hearing about how picky she was. Well...within a month of being here, sticking her nose up in the air at feeding times, she was the first own down and would literally grab the cookie sheet full of my ig salad (which did not contain her "she'll only eat _____" foods!) or the storage bowl out of my hands in her zeal to be the first to stick her face in it, wolfing it down 2-3 times a day! The other iguanas learned to just not bother moving from their places until Iguanita was done or almost done. When Wally, the alpha male, had decided that everyone had waited long enough, he would shift his body a bit, signaling to Iguanita that it was time to either back off or let some others in to eat...which she then did. (Sadly, one of Iguanita's favorite foods before she came to me was monkey biscuits. She died of kidney failure at age four.)

Truly Problem Cases
There are fewer of these than people think. An otherwise healthy (low/no parasites, well hydrated, well fleshed) iguana can go several weeks without eating. Iguanas are masters at energy conservation. They don't do much moving around anyway during the course of a day - they will just do even less when they are not eating.

A true problem iguana is one who was sick to begin with, who may not have been well fleshed to begin with, and who may be undergoing treatment for parasites, dehydration, and or metabolic bone disease. They may have been starved, intentionally or otherwise, by their former owners or the pet store.

If you've not taken such an iguana to a reptile vet, do so. Forcing a sick and dehydrated iguana to eat hard to digest food could send it into shock, or worse.

An iguana suffering from MBD or chronic starvation may not have a gut that is functioning very well. Much of its natural gut flora may have died off. Spoon feed a teaspoonful of nonfat yogurt containing live cultures once a day for a couple of days. This is very easy to digest and will help boost the gut flora.


Emaciation and Force-Feeding
Emaciated iguanas, or those severely weakened, from illness or starvation, should be started on an easy to digest high calorie food. The human nutritional product Ensure (available in the U.S. in grocery and drug stores) can be mixed with a crushed Centrum vitamin and a mashed banana (this makes the so-called "Ensure shake"). Ensure comes in many flavors in several different formulas - select the regular formula, not high protein or low fat formulas. It can be offered by spoon, eye dropper or needle-less syringe.

Important note: Forcing food into a dehydrated or starved lizard (and most starved lizards are also dehydrated) could make matters worse, so before actually force-feeding your iguana, be sure the read the articles on Fluids & Fluid Therapy in Reptiles, and Emaciation (Starvation) Protocol.

Gently pull down the dewlap and deposit a small amount in the mouth. Take it slow and easy. If you put too much in at one time or don't allow adequate time for swallowing, they may aspirate the fluid - literally inhale it or not be strong enough to react in time to close off the glottis leading to their lungs. Once food gets into the lungs, bacterial infection usually sets in which can be fatal if not treated. Too much fluid in there all at once may literally drown the iguana (this goes for most reptiles, actually). Be patient and plant to spend at least 15-20 minutes at each feeding session.

Iguanas will usually start to lap it up off the end of the syringe or eye dropper and can soon be encouraged to lap it up from a shallow plate or bowl. After a day or two of several such feedings a day, mix a very small amount of the iguana salad into the Ensure shake. Everyday, add a little bit more salad. Eventually, you will end up with more salad than Ensure, and ultimately wean out the Ensure completely. Ensure is a fatty food and so be sure to add your calcium supplement to the salad. The use of Ensure is for emergency measures only - it is not to be used as a staple food source.


In closing...
Just remember: you are bigger and supposedly too smart to fall for manipulative games played by a little green lizard!

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