behavioral problem

Question
I have a 7yrs old yellow belly male, which I've had him for 6 yrs. His habitate is an 80 gal tank with a canister filer. It has turtle river rocks for substrate and them misc rocks and plastic plants for decor. He has one light deducated for his tropical UVB light (ExoTerra Reptile UVB 100, 26w) which was changed May 21, 2015. For basking he has a dedicated light for basking (ZooMed Repti-Basking spot lamp, 75; changed April 2015). He diet consists of block food and every other night he get a 1/2  piece of ham (lunch meat style).

Now that you have the facts of his eating and habitate let's get down to the problem.  For the past 2-3 days I have noticed he was swimming backward a lot - like he is scared of something.  He is aggressived in his tank, meaning moving the big rocks around and he seems to be banging into the sides of the tank alot.  He seems confused, scared and agressive in his tank. Just today I got him out of his tank and he always loves to be around me, but this time when he crawled up on my shoulders he bit my ear and my hair.  He was hissing a lot, which he never hisses at  me, nor does he bit me. He seemed defensive and aggressive along with being a bit agitated. So, I put him back in his tank. I removed all the decorations except the substrate out to see what he would do. He did settle down a bit. After a little white he was acting like he wanted to come out with me again, so right now he is out of his tank, but I'm not paying attention to him.Just now he came up to me acting normal and wanting to come up on me. So I picked him up slowly and he bit my chin, so he is back on the floor.  This is not his normal behavior. For 6 years, besides today, he has bit me 1 other time and always wants to be on or around me.  Could his basking light need changed? He is so darn aggressive - I can hardly think that the basking light would be the problem.  Help pleae?

Answer
Hi Pati,

A change in behavior like that could indicate parasites, skin infection or irritation, or possibly something else.  If you haven't done a good tamk cleaning for a while, I'd do that first.  Also inspect him closely for any shell or skin fungus, abrasions, rot, etc.

I would change the lighting.  The Exo-Terra UVB bulbs have pretty poor output.  Get a ZooMed Powersun 100 watt instead, and then you don't need a separate basking bulb.   

You also need to imorove his diet.  I'm not sure what you mean by block food, but lunch meat is an absolutely horrible food for turtles.  His diet should consist of pellets (Reptomin or similar), animal protein, and greens/veggies.  Sliders are fairly carnivorous as juveniles, but consume more vegetable matter as they mature, so your turtle should definitely be getting vegetation several times a week.  Adding waterplants to the tank is another option, although they'll get eaten, of course.  I'll give you some links below with complete diet suggestions.  The main thing is variety, and lots of it.  

If you still notice a change after tank cleaning, etc., it would probably be worthwhile having a fecal check done for parasites.  One other possibility, and obviously this is only if you're not 100% he's male, is eggs.  Females will often become agitated/aggressive just before laying.

More information ((some of it is for RES, but works for YBS as well):

http://www.redearslider.com/
http://www.austinsturtlepage.com/Care/caresheet-red_ear_slider.htm
http://www.austinsturtlepage.com/Care/cs-yellowbelly.htm