I received the following question via e-mail.  The answer following it
is not exactly the same as I originally gave to the writer - it is a
combination of several answers I gave to similar questions.  I hope it
helps "shed" light on a subject frequently questioned.


> I have an iguana about 4 feet in length, he is not eating very well.
> I did not see bananas mentioned on your page and was wondering if there
> is a problem with feeding them.  Any sugestions would be appreciated.

Bananas are loved by iguanas, but they are not very good for them.  They
contain very little calcium and are pretty high in phosphorus.  In
general, fruits should be a small part of your iguana's diet.  See my
iguana guide for a sample recipe that is well-balanced for iguanas.

Here are some possible reasons for not eating:

  1) Not warm enough, especially right after feeding.  You should feed
     in the morning and he should have a warm basking light all day.
     A thermometer placed under the light should read in the 90s (F).
     There should also be a cooler spot that he can go to if he gets
     too warm.  Use a light bulb shining down from above, don't use a
     "hot rock".

  2) Stress.  If he has moved recently, or had some other stressful
     situation, he may go off his food for a while.  He will start again
     when he feels comfortable.  One source of stress is not having
     enough darkness at night.  If you stay up late at night, put a
     cover over the cage.

  3) Sickness, especially Metabolic Bone Disease.  Visit a reptile vet.  See
     http://www.anapsid.org/mbd.html for more information on MBD.

  4) Shedding.  Iguanas often decrease their food when shedding.

  5) New/different food.  When ever I make a change in the recipe (maybe
     one item is not available and I substitute something else), it takes
     a while for Perry (my ig) to get used to it, sometimes a week or
     more.  During that time, it helps if I put a *little* bit of a
     favorite food on top.  Otherwise, just wait him out.  He won't starve
     himself to death unless he is already sick with something else.

  6) UV Lighting - you need a fluorescent tube that is specifically designed
     to emit UV-B light.  A regular "black-light" probably isn't good enough.
     Also, you can't use a screw-in "full spectrum" bulb.  Something like a
     "Repti-Sun" or "Iguana Light" from Zoo-Med.  You don't need this
     right away, but don't wait too many weeks either.  See my web page for
     where to buy it.

  7) Sickness - he could be ill and need the care of a vet.  It is a good idea
     to take him to the vet anyway when you first get him.  You should find a
     vet that knows something about iguanas.

Assuming that the environment and health aren't causing it, the most
common cause of new iguanas not eating is that they don't understand
that the stuff you're offering is food.

The thing to do is find out from the previous owner exactly what they
fed him.  If need be, go there and actually get a small amount of it.
Sometimes, pet stores don't have their animals in stock long enough for
them to have eaten, and they usually don't know what the breeders fed
them.  If that's the case, you have little choice but to guess.  Get dark
green leaf lettuce and tear off one-inch square peices.  Skatter 5 or
6 of them around the cage (sometimes they're used to foraging).

Hopefully, you end up with *something* that he will eat readily.

Then the trick is moving him from that low-quality diet to a well-
balanced recipe.  Put a good amount of the good stuff in a bowl.
Add a 3 or 4 peices of his old food on top.  He should quickly
gobble up the old stuff, and take one bite (maybe two) of the good
stuff.  He will then say, "ugh, that's not real food" and stop.

A little later (10-15 minutes), take away the bowl, put some more of
his old food on top and give it back.  The same thing should happen.
After that second round, leave the bowl for the rest of the day.

On subsequent days, repeat the above sequence, progresively using smaller
and smaller amounts of the old food on top.  Within a week, he should be
at the point where he will grudgingly eat some of the good stuff without
any of the old stuff.

A couple of weeks after that, he should be eating normally.