Abnormal behavior -- Yellow Belly Slider

Question
My 5-year-old female yellow-bellied slider has now not eaten in 10 days, will not come out of the pond to bask, and will not even swim to the surface of the pond (extremely unusual behavior for a normally very social turtle).  I live in Florida, the weather is in the 70's during the day, 60's at night.  She is in a 750 gallon pond that is 2.5 feet deep.  She also will just float to the bottom of the pond and will not come up, looks like she wants to but can't.  (She is normally a very social turtle who is up and out of the pond or mooching food as soon as she sees someone).

I took her to the vet, all her blood work came back normal, they kept her for observation, and she appeared normal in their incubator, heat lamp set-up.  She would not eat for them either.  I have been keeping her indoors using a window and regular lamp for light, and a infrared lamp for heat.  Then, during the warmest part of the day, I will take her outside to see if she will eat or bask.  Every day she just walks right to the pond, jumps in then within a minute or two drops to the bottom.  

Her behavior did seem to start during a relative cold snap (it got down to the high 30's for a few days).  It is almost like she went into a semi-hibernation stage, but then did not come out of it when the weather warmed.

I have had her since she was a baby, and she has been in this same pond for three years, all year long and has never acted like this before.  Per the blood work, she has not reached sexual maturity and is not starting a reproduction cycle.

She is on antibiotics -- injection of Fortaz 100 mg, every 72 hrs.  The vet has no idea why she is acting like this, but is not very concerned, given that her clinical observations and blood work indicate a healthy turtle.

I'm getting very concerned, however.  Do you have any ideas??  Thank you very much for your help.


Do you have any ideas as to what could be wrong with her?  Not eating and lethargy are just not like her.  I did notice today that she was pawing at her mouth, but that did happen right after I tried to give her an injection.

Answer
My thoughts are all centered around the cold snap. I don't think this is a semi-hibernation, I think it is more like a case of hypothermia and things have not been warm and sunny enough afterwards to knock it out of it.

Your turtle is still pretty young, and small enough that the chill could have caused some problems.

I would try bringing it in, putting it in a big tub (say a 50 gallon plastic tub mostly filled), warm the water to 80-85F, and offer some UVB lighting or unfiltered sunlight. I would also add some Stress Coat (fish medicine) to the water  to help. It may take a week to see it get over things. (A good submersible heater in the pond may be enough to make a warm pocket for it- but that is just a guess.)

If this is the solution, it should show improvement in a few days, then you can slowly ease the temps back to the pond over the course of a month.