Turtle has brown spot on back of neck

Question
I have 2 I think they are called Alabama cooters, anyway one I noticed the male that is has a brownish ruff spot on the back of his neck ( kind of puffy and flaky looking) right where his neck rolls over when he is tucked inside it looks like it hits his shell when he pulls his head in but I also noticed that the female has been biting him around that same area.  Any info on what I should do or if I should just leave it alone and watch it a while longer it is new I have never noticed it before and they are where you see them every day almost all day.

Answer
Aggression that causes injuries is always a concern, and often a sign that they feel crowded. Try a larger tank- aim for 10 gallons of water per inch of turtle shell length.

This seems like a lot to many keepers, but remember that these are swimming animals that rarely have to be close to each other unless they are sharing a basking site.

Try http://www.austinsturtlepage.com for some good care info and articles that can also help.